:root {
    --bg-primary: #ffffff;
    --bg-secondary: #f8f9fa;
    --bg-tertiary: #f1f3f4;
    --text-primary: #202124;
    --text-secondary: #5f6368;
    --text-tertiary: #80868b;
    --border-color: #dadce0;
    --accent-color: #1a73e8;
    --accent-hover: #1557b0;
    --shadow-sm: 0 1px 2px 0 rgba(60, 64, 67, 0.3), 0 1px 3px 1px rgba(60, 64, 67, 0.15);
    --shadow-md: 0 1px 2px 0 rgba(60, 64, 67, 0.3), 0 2px 6px 2px rgba(60, 64, 67, 0.15);
    --shadow-lg: 0 2px 4px 0 rgba(60, 64, 67, 0.3), 0 4px 8px 3px rgba(60, 64, 67, 0.15);
    --input-bg: #ffffff;
    --input-border: #dadce0;
    --input-focus: #1a73e8;
    --button-bg: #1a73e8;
    --button-hover: #1557b0;
    --button-text: #ffffff;
    --warning-bg: #fef7e0;
    --warning-border: #fbbc04;
    --warning-text: #ea8600;
    --message-own-bg: #1a73e8;
    --message-other-bg: #f1f3f4;
    --message-own-text: #ffffff;
    --message-other-text: #202124;
    --modal-bg: #ffffff;
    --modal-text: #202124;
    --ad-bg: #f8f9fa;
    --ad-border: #dadce0;
    --ad-text: #5f6368;
}

[data-theme="dark"] {
    --bg-primary: #202124;
    --bg-secondary: #303134;
    --bg-tertiary: #3c4043;
    --text-primary: #e8eaed;
    --text-secondary: #bdc1c6;
    --text-tertiary: #9aa0a6;
    --border-color: #5f6368;
    --accent-color: #8ab4f8;
    --accent-hover: #aecbfa;
    --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.3), 0 1px 3px 1px rgba(0, 0, 0, 0.15);
    --shadow-md: 0 1px 2px 0 rgba(0, 0, 0, 0.3), 0 2px 6px 2px rgba(0, 0, 0, 0.15);
    --shadow-lg: 0 2px 4px 0 rgba(0, 0, 0, 0.3), 0 4px 8px 3px rgba(0, 0, 0, 0.15);
    --input-bg: #303134;
    --input-border: #5f6368;
    --input-focus: #8ab4f8;
    --button-bg: #8ab4f8;
    --button-hover: #aecbfa;
    --button-text: #202124;
    --warning-bg: #3c341f;
    --warning-border: #fbbc04;
    --warning-text: #fdd663;
    --message-own-bg: #8ab4f8;
    --message-other-bg: #303134;
    --message-own-text: #202124;
    --message-other-text: #e8eaed;
    --modal-bg: #303134;
    --modal-text: #e8eaed;
    --ad-bg: #303134;
    --ad-border: #5f6368;
    --ad-text: #9aa0a6;
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: 'Google Sans', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
    background-color: var(--bg-primary);
    color: var(--text-primary);
    padding: 20px;
    transition: background-color 0.3s ease, color 0.3s ease;
}

[data-device-type="mobile"] body {
    padding: 0;
    overflow: hidden;
}

[data-device-type="mobile"] .container {
    width: 100%;
    max-width: 100%;
    height: 100vh;
    height: 100dvh;
    height: calc(var(--vh, 1vh) * 100);
    overflow: hidden;
    position: relative;
}

[data-device-type="mobile"] .chat-container:not(.hidden) ~ .page-header,
[data-device-type="mobile"] .chat-container:not(.hidden) ~ .tabs,
[data-device-type="mobile"] .chat-container:not(.hidden) ~ .join-form,
[data-device-type="mobile"] .chat-container:not(.hidden) ~ .active-rooms {
    display: none !important;
}

.device-ios {
    -webkit-overflow-scrolling: touch;
}

.device-ios input,
.device-ios textarea,
.device-ios select {
    font-size: 16px;
}

.device-ios button {
    -webkit-tap-highlight-color: transparent;
}

.device-android {
    -webkit-overflow-scrolling: touch;
}

.device-android button {
    -webkit-tap-highlight-color: transparent;
}

.high-dpi {
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

[data-touch="true"] button,
[data-touch="true"] .theme-toggle,
[data-touch="true"] .leave-button,
[data-touch="true"] #joinButton,
[data-touch="true"] #sendButton {
    min-height: 44px;
    min-width: 44px;
}

[data-touch="true"] .message-bubble {
    user-select: text;
    -webkit-user-select: text;
}

[data-orientation="landscape"][data-device-type="mobile"] .chat-container {
    height: 100vh;
    height: 100dvh;
    height: calc(var(--vh, 1vh) * 100);
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    min-height: 0;
    overflow: hidden;
}

[data-orientation="landscape"][data-device-type="mobile"] .messages {
    padding: 12px;
    min-height: 0;
}

[data-orientation="landscape"][data-device-type="mobile"] .chat-header {
    padding: 8px 16px;
}

[data-orientation="landscape"][data-device-type="mobile"] .chat-input-container {
    padding: 10px 16px;
}

[data-browser="safari"] .messages {
    scrollbar-width: none;
    -ms-overflow-style: none;
}

[data-browser="safari"] .messages::-webkit-scrollbar {
    display: none;
}

[data-device-type="tablet"] .join-form {
    max-width: 600px;
}

[data-device-type="tablet"] .chat-container {
    max-width: 900px;
}

[data-device-type="desktop"] .theme-toggle:hover {
    box-shadow: 0 2px 6px rgba(0, 0, 0, 0.15), 0 1px 3px rgba(0, 0, 0, 0.3);
    transform: translateY(-1px);
}

.container {
    width: 100%;
    max-width: 1200px;
    margin: 0 auto;
}

@media (min-width: 1400px) {
    body {
        padding: 20px 0;
    }
    
    .container {
        max-width: 1600px;
        width: 100%;
        padding: 0 20px;
    }
    
    .chat-container {
        max-width: 1600px;
    }
    
    .ad-top,
    .ad-bottom {
        max-width: 970px;
    }
    
    .ad-sidebar {
        width: 200px;
    }
}

@media (min-width: 1920px) {
    body {
        padding: 20px 0;
    }
    
    .container {
        max-width: 1800px;
        width: 100%;
        padding: 0 40px;
    }
    
    .chat-container {
        max-width: 1800px;
    }
    
    .ad-top,
    .ad-bottom {
        max-width: 970px;
    }
    
    .ad-sidebar {
        width: 250px;
    }
}

.page-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 16px;
    padding: 12px 0;
}

.theme-toggle {
    padding: 10px 20px;
    border-radius: 24px;
    border: none;
    background-color: #137333;
    color: #ffffff;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 14px;
    font-weight: 500;
    font-family: 'Google Sans', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
    box-shadow: 0 1px 3px rgba(0, 0, 0, 0.12), 0 1px 2px rgba(0, 0, 0, 0.24);
    transition: all 0.2s ease;
    white-space: nowrap;
}

.theme-toggle:hover {
    box-shadow: 0 2px 6px rgba(0, 0, 0, 0.15), 0 1px 3px rgba(0, 0, 0, 0.3);
    transform: translateY(-1px);
}

.theme-toggle:active {
    transform: translateY(0);
    box-shadow: 0 1px 2px rgba(0, 0, 0, 0.2);
}

.site-logo {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    font-size: 28px;
    font-weight: 700;
    color: var(--text-primary);
    text-decoration: none;
    padding: 10px 14px;
    border-radius: 8px;
    transition: all 0.2s ease;
}

.site-logo:hover {
    background: var(--bg-tertiary);
    color: var(--accent-color);
}

.theme-text {
    font-size: 14px;
    font-weight: 500;
    color: #ffffff;
}

[data-theme="dark"] .theme-toggle {
    background-color: #8ab4f8;
    color: #202124;
}

[data-theme="dark"] .theme-text {
    color: #202124;
}

.ad-container {
    border-radius: 8px;
    overflow: hidden;
    background-color: var(--ad-bg);
    border: 1px solid var(--ad-border);
    min-height: 0;
    text-align: center;
    flex-shrink: 0;
}

.ad-container:empty,
.ad-container.hidden,
.ad-container .adsbygoogle[data-ad-status="unfilled"] {
    display: none !important;
}

.ad-container .adsbygoogle:not([data-ad-status]) {
    display: none !important;
}

.ad-top {
    max-width: 728px;
    min-height: 0;
    margin: 0;
    padding: 0;
}

.ad-bottom {
    max-width: 728px;
    min-height: 0;
    margin: 0;
    padding: 0;
    flex-shrink: 0;
}

.keyboard-visible .ad-bottom {
    display: none !important;
}

.keyboard-visible .chat-container {
    position: fixed !important;
    top: 0 !important;
    left: 0 !important;
    right: 0 !important;
    bottom: 0 !important;
    height: 100vh !important;
    height: 100dvh !important;
    margin: 0 !important;
    border-radius: 0 !important;
}

.keyboard-visible .chat-input-container {
    position: fixed !important;
    left: 0 !important;
    right: 0 !important;
    z-index: 1000 !important;
    background-color: var(--bg-primary) !important;
    border-top: 1px solid var(--border-color) !important;
    transform: translateZ(0);
    -webkit-transform: translateZ(0);
    /* bottomはJavaScriptで動的に設定するため、!importantを削除 */
}

.keyboard-visible .chat-input-container input {
    transform: translateZ(0);
    -webkit-transform: translateZ(0);
}

.keyboard-visible .messages {
    overflow-y: auto !important;
    -webkit-overflow-scrolling: touch !important;
}

[data-device-type="mobile"].keyboard-visible body {
    overflow: hidden !important;
    position: fixed !important;
    width: 100% !important;
    height: 100vh !important;
    height: 100dvh !important;
    top: 0 !important;
    left: 0 !important;
}

[data-device-type="mobile"].keyboard-visible .container {
    height: 100vh;
    height: 100dvh;
    overflow: hidden;
}

.ad-sidebar {
    width: 160px;
    min-height: 600px;
    margin-right: 20px;
    flex-shrink: 0;
}

.ad-placeholder {
    width: 100%;
    height: 100%;
    display: flex;
    align-items: center;
    justify-content: center;
    background-color: var(--ad-bg);
    border: 2px dashed var(--ad-border);
    border-radius: 8px;
}

.ad-label {
    color: var(--ad-text);
    font-size: 14px;
    font-weight: 500;
}

.stats-bar {
    margin-top: 24px;
    text-align: right;
    color: var(--text-secondary);
    font-size: 14px;
}

.stats-bar.hidden {
    display: none;
}

.tabs {
    display: flex;
    gap: 8px;
    margin-bottom: 16px;
}

.tabs.hidden {
    display: none;
}

.tab-button {
    padding: 10px 16px;
    border-radius: 8px;
    border: 1px solid var(--border-color);
    background: var(--bg-secondary);
    color: var(--text-primary);
    cursor: pointer;
    font-weight: 600;
    transition: all 0.2s ease;
}

.tab-button--active {
    background: var(--accent-color);
    color: var(--button-text);
    border-color: var(--accent-color);
    box-shadow: var(--shadow-sm);
}

.tab-button:hover {
    box-shadow: var(--shadow-sm);
}

.active-rooms {
    margin-top: 16px;
    padding: 16px;
    border: 1px solid var(--border-color);
    border-radius: 8px;
    background: var(--bg-secondary);
    box-shadow: var(--shadow-sm);
}

.active-rooms.hidden {
    display: none;
}

.active-rooms__header {
    display: flex;
    justify-content: space-between;
    align-items: baseline;
    margin-bottom: 8px;
    gap: 12px;
}

.active-rooms__title {
    font-size: 16px;
    font-weight: 600;
    color: var(--text-primary);
}

.active-rooms__subtitle {
    font-size: 12px;
    color: var(--text-tertiary);
}

.active-rooms__hint {
    font-size: 12px;
    color: var(--text-tertiary);
    margin: 4px 0 10px;
}

.active-rooms__list {
    list-style: none;
    margin: 0;
    padding: 0;
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(180px, 1fr));
    gap: 8px;
}

.active-rooms__item {
    padding: 10px 12px;
    border: 1px solid var(--border-color);
    border-radius: 8px;
    background: var(--bg-primary);
    display: flex;
    flex-direction: column;
    gap: 6px;
    transition: transform 0.1s ease, box-shadow 0.1s ease;
    cursor: pointer;
}

.active-rooms__item:hover {
    box-shadow: var(--shadow-sm);
    transform: translateY(-1px);
}

.active-rooms__name {
    font-size: 14px;
    color: var(--text-primary);
}

.active-rooms__count {
    font-size: 13px;
    color: var(--text-secondary);
    flex-shrink: 0;
}

.active-rooms__header-row {
    display: flex;
    justify-content: space-between;
    align-items: center;
    width: 100%;
    gap: 8px;
}

.active-rooms__toggle {
    border: 1px solid var(--border-color);
    background: var(--bg-secondary);
    color: var(--text-primary);
    border-radius: 6px;
    padding: 4px 8px;
    cursor: pointer;
    font-size: 12px;
    align-self: flex-start;
}

.active-rooms__members {
    list-style: none;
    margin: 0;
    padding-left: 12px;
    display: flex;
    flex-direction: column;
    gap: 4px;
    color: var(--text-primary);
    display: none;
}

.active-rooms__members.hidden {
    display: none;
}

.active-rooms__members-empty {
    color: var(--text-tertiary);
    font-size: 12px;
}

.active-rooms__empty {
    margin-top: 8px;
    color: var(--text-tertiary);
    font-size: 13px;
}

.copy-toast {
    margin-top: 10px;
    padding: 8px 12px;
    background: var(--bg-tertiary);
    border: 1px solid var(--border-color);
    border-radius: 6px;
    color: var(--text-primary);
    font-size: 13px;
    box-shadow: var(--shadow-sm);
}

.copy-toast.hidden {
    display: none;
}

.join-form {
    background: var(--bg-primary);
    border-radius: 8px;
    box-shadow: var(--shadow-md);
    padding: 48px;
    animation: fadeIn 0.3s ease-in;
    border: 1px solid var(--border-color);
    max-width: 500px;
    margin: 0 auto;
}

.join-form.hidden {
    display: none !important;
}

.form-container h1 {
    color: var(--text-primary);
    margin-bottom: 32px;
    text-align: center;
    font-size: 32px;
    font-weight: 400;
    letter-spacing: -0.5px;
}

.warning-box {
    background: var(--warning-bg);
    border: 1px solid var(--warning-border);
    border-radius: 8px;
    padding: 16px;
    margin-bottom: 32px;
}

.warning-box strong {
    color: var(--warning-text);
    display: block;
    margin-bottom: 8px;
    font-size: 14px;
    font-weight: 500;
}

.warning-box p {
    color: var(--warning-text);
    font-size: 14px;
    line-height: 1.5;
    margin: 0;
}

.form-group {
    margin-bottom: 24px;
}

.form-group label {
    display: block;
    margin-bottom: 8px;
    color: var(--text-secondary);
    font-weight: 500;
    font-size: 14px;
}

.form-group input {
    width: 100%;
    padding: 12px 16px;
    border: 1px solid var(--input-border);
    border-radius: 4px;
    font-size: 16px;
    background-color: var(--input-bg);
    color: var(--text-primary);
    transition: border-color 0.2s, box-shadow 0.2s;
}

.form-group input:focus {
    outline: none;
    border-color: var(--input-focus);
    box-shadow: 0 0 0 2px rgba(26, 115, 232, 0.2);
}

.form-group input::placeholder {
    color: var(--text-tertiary);
}

#joinButton {
    width: 100%;
    padding: 12px 24px;
    background: var(--button-bg);
    color: var(--button-text);
    border: none;
    border-radius: 4px;
    font-size: 16px;
    font-weight: 500;
    cursor: pointer;
    transition: background-color 0.2s, box-shadow 0.2s;
    margin-top: 8px;
}

#joinButton:hover {
    background: var(--button-hover);
    box-shadow: var(--shadow-sm);
}

#joinButton:active {
    box-shadow: none;
}

.chat-container {
    background: var(--bg-primary);
    border-radius: 8px;
    box-shadow: var(--shadow-md);
    display: flex;
    flex-direction: column;
    height: 800px;
    animation: fadeIn 0.3s ease-in;
    border: 1px solid var(--border-color);
    max-width: 1200px;
    margin: 0 auto;
    min-height: 0;
    overflow: hidden;
}

.chat-container.hidden {
    display: none;
}

.chat-header {
    background: var(--bg-secondary);
    color: var(--text-primary);
    padding: 16px 24px;
    border-radius: 8px 8px 0 0;
    display: flex;
    justify-content: space-between;
    align-items: center;
    border-bottom: 1px solid var(--border-color);
    flex-shrink: 0;
}

.chat-header__left {
    display: flex;
    flex-direction: column;
    gap: 8px;
    flex: 1;
    min-width: 0;
}

.chat-header__left > h2 {
    margin: 0;
}

.user-icon-upload-section {
    display: flex;
    align-items: center;
    gap: 12px;
}

.user-icon-preview-container {
    position: relative;
    width: 64px;
    height: 64px;
    border-radius: 50%;
    overflow: hidden;
    background: var(--bg-tertiary);
    border: 2px solid var(--border-color);
    display: flex;
    align-items: center;
    justify-content: center;
    flex-shrink: 0;
}

.user-icon-preview {
    width: 100%;
    height: 100%;
    object-fit: cover;
}

.user-icon-placeholder {
    width: 100%;
    height: 100%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 32px;
    color: var(--text-secondary);
    font-weight: bold;
}

.user-icon-upload-controls {
    display: flex;
    flex-direction: column;
    gap: 8px;
    flex: 1;
}

.user-icon-upload-button,
.user-icon-remove-button {
    padding: 8px 16px;
    border: 1px solid var(--border-color);
    border-radius: 6px;
    background: var(--bg-secondary);
    color: var(--text-primary);
    cursor: pointer;
    font-size: 14px;
    font-weight: 500;
    transition: all 0.2s ease;
}

.user-icon-upload-button:hover {
    background: var(--bg-tertiary);
    box-shadow: var(--shadow-sm);
}

.user-icon-remove-button {
    background: var(--bg-tertiary);
}

.user-icon-remove-button:hover {
    background: var(--bg-primary);
    box-shadow: var(--shadow-sm);
}

.user-icon-remove-button.hidden {
    display: none;
}

.chat-header h2 {
    font-size: 20px;
    font-weight: 400;
    color: var(--text-primary);
    margin: 0;
    white-space: nowrap;
    line-height: 1.2;
}

.room-members-inline {
    display: flex;
    align-items: center;
    gap: 6px;
    flex: 1;
    min-width: 0;
    overflow: hidden;
}

.room-members-inline__list {
    display: flex;
    align-items: center;
    gap: 6px;
    flex-wrap: nowrap;
    overflow: hidden;
}

.room-members-inline__chip {
    padding: 4px 8px;
    background: var(--bg-tertiary);
    border: 1px solid var(--border-color);
    border-radius: 12px;
    font-size: 12px;
    color: var(--text-primary);
    white-space: nowrap;
    flex-shrink: 0;
}

.room-members-inline__more {
    padding: 4px 8px;
    background: var(--bg-tertiary);
    border: 1px solid var(--border-color);
    border-radius: 12px;
    font-size: 12px;
    color: var(--accent-color);
    cursor: pointer;
    white-space: nowrap;
    flex-shrink: 0;
    user-select: none;
}

.room-members-inline__more:hover {
    background: var(--bg-primary);
    box-shadow: var(--shadow-sm);
}

.room-members-expanded {
    background: var(--bg-secondary);
    padding: 12px 24px;
    border-bottom: 1px solid var(--border-color);
    flex-shrink: 0;
}

.room-members-expanded.hidden {
    display: none;
}

.room-members-expanded__list {
    display: flex;
    flex-wrap: wrap;
    gap: 6px;
}

.room-members-expanded__chip {
    padding: 6px 10px;
    background: var(--bg-primary);
    border: 1px solid var(--border-color);
    border-radius: 16px;
    font-size: 13px;
    color: var(--text-primary);
    box-shadow: var(--shadow-sm);
}

.room-members {
    position: relative;
}

.header-actions .room-members {
    padding: 0;
    border-bottom: none;
    background: transparent;
}

.room-members__toggle {
    border: 1px solid var(--border-color);
    background: var(--bg-tertiary);
    color: var(--text-primary);
    border-radius: 6px;
    padding: 6px 10px;
    cursor: pointer;
    font-size: 13px;
}

.room-members__list {
    position: absolute;
    top: 100%;
    right: 0;
    margin-top: 8px;
    padding: 10px 16px;
    background: var(--bg-secondary);
    border: 1px solid var(--border-color);
    border-radius: 8px;
    box-shadow: var(--shadow-md);
    display: flex;
    flex-wrap: wrap;
    gap: 6px;
    color: var(--text-primary);
    z-index: 100;
    min-width: 200px;
    max-width: 400px;
}

.room-members__chip {
    padding: 6px 10px;
    background: var(--bg-primary);
    border: 1px solid var(--border-color);
    border-radius: 16px;
    font-size: 13px;
    color: var(--text-primary);
    box-shadow: var(--shadow-sm);
}

.room-members.collapsed .room-members__list {
    display: none;
}

.header-actions {
    display: flex;
    gap: 12px;
    align-items: center;
}

.leave-button {
    background: var(--bg-tertiary);
    color: var(--text-primary);
    border: 1px solid var(--border-color);
    padding: 8px 16px;
    border-radius: 4px;
    cursor: pointer;
    font-size: 14px;
    font-weight: 500;
    transition: background-color 0.2s, box-shadow 0.2s;
}

.leave-button:hover {
    background: var(--bg-tertiary);
    box-shadow: var(--shadow-sm);
}

.chat-content-wrapper {
    display: flex;
    flex: 1;
    overflow: hidden;
    position: relative;
    min-height: 0;
}

.messages {
    flex: 1;
    overflow-y: auto;
    padding: 24px;
    background: var(--bg-primary);
    min-height: 0;
}

.room-members-sidebar {
    width: 250px;
    background: var(--bg-secondary);
    border-left: 1px solid var(--border-color);
    display: flex;
    flex-direction: column;
    overflow: hidden;
    flex-shrink: 0;
}

.room-members-sidebar.hidden {
    display: none;
}

.room-members-sidebar__header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 16px;
    border-bottom: 1px solid var(--border-color);
    background: var(--bg-secondary);
}

.room-members-sidebar__title {
    font-size: 16px;
    font-weight: 600;
    color: var(--text-primary);
    margin: 0;
}

.room-members-sidebar__toggle {
    background: transparent;
    border: none;
    color: var(--text-secondary);
    font-size: 24px;
    cursor: pointer;
    padding: 4px 8px;
    border-radius: 4px;
    transition: background-color 0.2s ease, color 0.2s ease;
    line-height: 1;
    width: 32px;
    height: 32px;
    display: flex;
    align-items: center;
    justify-content: center;
}

.room-members-sidebar__toggle:hover {
    background: var(--bg-tertiary);
    color: var(--text-primary);
}

.room-members-sidebar-open {
    background: var(--bg-tertiary);
    color: var(--text-primary);
    border: 1px solid var(--border-color);
    padding: 8px 12px;
    border-radius: 4px;
    cursor: pointer;
    font-size: 16px;
    font-weight: 500;
    transition: background-color 0.2s, box-shadow 0.2s;
    display: flex;
    align-items: center;
    justify-content: center;
    min-width: 40px;
    min-height: 40px;
}

.room-members-sidebar-open:hover {
    background: var(--bg-primary);
    box-shadow: var(--shadow-sm);
}

.room-members-sidebar__content {
    flex: 1;
    overflow-y: auto;
    padding: 12px;
}

.room-members-sidebar__list {
    display: flex;
    flex-direction: column;
    gap: 8px;
}

.room-members-sidebar__item {
    padding: 10px 12px;
    background: var(--bg-primary);
    border: 1px solid var(--border-color);
    border-radius: 8px;
    color: var(--text-primary);
    font-size: 14px;
    transition: background-color 0.2s ease, box-shadow 0.2s ease;
}

.room-members-sidebar__item:hover {
    background: var(--bg-tertiary);
    box-shadow: var(--shadow-sm);
}

.room-members-sidebar__empty {
    padding: 20px;
    text-align: center;
    color: var(--text-tertiary);
    font-size: 14px;
}

.room-members-sidebar__empty.hidden {
    display: none;
}

.message {
    margin-bottom: 16px;
    animation: slideIn 0.3s ease-out;
    position: relative;
}

.message.system {
    text-align: center;
    color: var(--text-secondary);
    font-size: 13px;
    font-style: italic;
    padding: 8px;
    background: var(--bg-tertiary);
    border-radius: 6px;
    margin: 8px 0;
}

.message.chat {
    display: flex;
    flex-direction: row;
    align-items: flex-start;
    gap: 10px;
    padding-top: 14px;
    margin-bottom: 2px;
}

.message.chat.own {
    align-items: flex-start;
}

.message.chat.other {
    align-items: flex-start;
}

.message-content-wrapper {
    display: flex;
    flex-direction: column;
    flex: 1;
    min-width: 0;
    position: relative;
}


.message-bubble {
    max-width: 100%;
    padding: 0;
    border-radius: 0;
    word-wrap: break-word;
    position: relative;
    box-shadow: none;
    background: transparent;
    color: var(--text-primary);
    font-size: 16px;
    line-height: 1.5;
}

.message-images-container {
    display: flex;
    flex-wrap: wrap;
    gap: 8px;
    margin-bottom: 6px;
    justify-content: flex-start;
}

.message-image-container {
    border-radius: 8px;
    overflow: hidden;
    max-width: 100%;
    flex: 0 0 auto;
}

.message-image {
    max-width: min(520px, 80vw);
    max-height: 520px;
    height: auto;
    width: auto;
    display: block;
    border-radius: 8px;
    cursor: pointer;
    object-fit: contain;
    transition: opacity 0.2s ease;
    background: transparent;
    margin: 0;
}

.message-image:hover {
    opacity: 0.9;
}

.message.uploading {
    opacity: 0.8;
}

.message-image-container.uploading {
    position: relative;
    overflow: hidden;
}

.message-image.uploading {
    filter: brightness(0.9);
}

.upload-progress-overlay {
    position: absolute;
    bottom: 0;
    left: 0;
    right: 0;
    background: rgba(0, 0, 0, 0.6);
    backdrop-filter: blur(4px);
    padding: 8px;
    display: flex;
    flex-direction: column;
    gap: 4px;
    z-index: 10;
}

.upload-progress-bar {
    height: 4px;
    background: var(--accent-color);
    border-radius: 2px;
    transition: width 0.3s ease;
    box-shadow: 0 0 8px rgba(26, 115, 232, 0.5);
}

.upload-progress-text {
    color: #ffffff;
    font-size: 12px;
    font-weight: 500;
    text-align: center;
    text-shadow: 0 1px 2px rgba(0, 0, 0, 0.5);
}

[data-theme="dark"] .upload-progress-overlay {
    background: rgba(0, 0, 0, 0.7);
}

[data-theme="dark"] .upload-progress-bar {
    background: var(--accent-color);
    box-shadow: 0 0 8px rgba(138, 180, 248, 0.5);
}

.message-text {
    word-wrap: break-word;
    padding: 0;
    margin: 0;
    font-size: 16px;
    line-height: 1.5;
}

.message.chat.own .message-bubble {
    background: transparent;
    color: var(--text-primary);
}

.message.chat.other .message-bubble {
    background: transparent;
    color: var(--text-primary);
}

.message.image-only .message-bubble,
.message.image-only .message-content {
    background: transparent !important;
    padding: 0 !important;
    border-radius: 0 !important;
    border: none !important;
    box-shadow: none !important;
    max-width: 100% !important;
}

.message.image-only .message-images-container {
    margin-bottom: 0;
    margin-top: 0;
}

.message.image-only .message-content {
    margin-top: 0;
    padding-top: 0;
}

.message.image-only .message-content-wrapper {
    margin-top: 0;
}

.message.image-only .message-name {
    display: flex;
}

.message-name {
    display: flex;
    align-items: center;
    gap: 8px;
    font-size: 16px;
    color: var(--text-primary);
    margin-bottom: 4px;
    padding: 0;
    font-weight: 600;
}

.message-icon {
    width: 48px;
    height: 48px;
    border-radius: 50%;
    overflow: hidden;
    background: var(--bg-tertiary);
    border: 1px solid var(--border-color);
    display: flex;
    align-items: center;
    justify-content: center;
    flex-shrink: 0;
    margin-top: 2px;
}

.message-icon-img {
    width: 100%;
    height: 100%;
    object-fit: cover;
}

.message-icon-placeholder {
    font-size: 22px;
    color: var(--text-secondary);
    font-weight: bold;
}

.message-name__text {
    white-space: nowrap;
}

.message.chat.own .message-name {
    justify-content: flex-start;
}

.message.chat.other .message-name {
    justify-content: flex-start;
}

.message-mute-button {
    background: transparent;
    border: none;
    cursor: pointer;
    padding: 4px 6px;
    font-size: 14px;
    opacity: 0;
    transition: opacity 0.2s ease;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: 4px;
    margin-left: 4px;
    -webkit-tap-highlight-color: transparent;
}

.message-name:hover .message-mute-button {
    opacity: 0.6;
}

.message-mute-button:hover {
    opacity: 1 !important;
    background: var(--bg-tertiary);
}

.message-mute-button:active {
    transform: scale(0.95);
}

/* スマホ版ではミュートボタンを非表示（長押しメニューを使用） */
[data-device-type="mobile"] .message-mute-button,
[data-touch="true"] .message-mute-button {
    display: none;
}

/* ミュートメニュー */
.mute-menu {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    z-index: 10000;
    display: flex;
    align-items: center;
    justify-content: center;
}

.mute-menu.hidden {
    display: none;
}

.mute-menu-overlay {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.3);
    backdrop-filter: blur(2px);
}

.mute-menu-content {
    position: absolute;
    background: var(--modal-bg);
    border-radius: 12px;
    box-shadow: var(--shadow-lg);
    padding: 0;
    min-width: 200px;
    max-width: 90%;
    z-index: 10001;
    overflow: hidden;
}

.mute-menu-header {
    padding: 16px 20px;
    border-bottom: 1px solid var(--border-color);
    background: var(--bg-secondary);
}

.mute-menu-user-name {
    font-size: 16px;
    font-weight: 600;
    color: var(--text-primary);
}

.mute-menu-button {
    width: 100%;
    padding: 16px 20px;
    background: transparent;
    border: none;
    display: flex;
    align-items: center;
    gap: 12px;
    cursor: pointer;
    font-size: 16px;
    color: var(--text-primary);
    transition: background-color 0.2s ease;
    -webkit-tap-highlight-color: transparent;
}

.mute-menu-button:hover {
    background: var(--bg-tertiary);
}

.mute-menu-button:active {
    background: var(--bg-tertiary);
    opacity: 0.8;
}

.mute-menu-icon {
    font-size: 20px;
    flex-shrink: 0;
}

.mute-menu-text {
    flex: 1;
    text-align: left;
}

/* スマホ版のミュートメニュー */
[data-device-type="mobile"] .mute-menu-button,
[data-touch="true"] .mute-menu-button {
    min-height: 48px;
    padding: 16px 20px;
}

[data-device-type="mobile"] .mute-menu-content,
[data-touch="true"] .mute-menu-content {
    min-width: 240px;
    border-radius: 16px;
}

.message-time {
    font-size: 13px;
    color: var(--text-secondary);
    white-space: nowrap;
}

.message.chat.other .message-time {
    text-align: left;
}

.chat-input-container {
    display: flex;
    flex-direction: column;
    padding: 16px 24px;
    border-top: 1px solid var(--border-color);
    background: var(--bg-primary);
    border-radius: 0 0 8px 8px;
    gap: 12px;
    flex-shrink: 0;
}

[data-device-type="mobile"] .ad-bottom {
    display: none !important;
}

.image-preview-container {
    margin-bottom: 8px;
    display: none;
}

.image-preview-container:not(.hidden) {
    display: block;
}

.image-preview-list {
    display: flex;
    flex-wrap: wrap;
    gap: 8px;
}

.image-preview-item {
    position: relative;
    max-width: 120px;
}

.image-preview-img {
    max-width: 100%;
    max-height: 120px;
    border-radius: 8px;
    border: 1px solid var(--border-color);
    display: block;
    object-fit: cover;
}

.image-preview-container.hidden {
    display: none !important;
}

.image-preview-container.hidden * {
    display: none !important;
}

.image-preview-item .image-preview-cancel {
    position: absolute;
    top: -8px;
    right: -8px;
    width: 24px;
    height: 24px;
    border-radius: 50%;
    background: var(--bg-primary);
    border: 1px solid var(--border-color);
    color: var(--text-primary);
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 18px;
    line-height: 1;
    box-shadow: var(--shadow-sm);
    z-index: 10;
}

.image-preview-item .image-preview-cancel:hover {
    background: var(--bg-tertiary);
}

.input-row {
    display: flex;
    align-items: center;
    gap: 8px;
}

.image-button {
    padding: 10px 14px;
    background: var(--bg-tertiary);
    border: 1px solid var(--border-color);
    border-radius: 8px;
    color: var(--text-primary);
    cursor: pointer;
    transition: all 0.2s ease;
    flex-shrink: 0;
    display: flex;
    align-items: center;
    justify-content: center;
    width: 44px;
    height: 44px;
    padding: 0;
}

.image-button svg {
    width: 20px;
    height: 20px;
    display: block;
}

.image-button:hover {
    background: var(--bg-primary);
    box-shadow: var(--shadow-sm);
}

#messageInput {
    flex: 1;
    padding: 12px 16px;
    border: 1px solid var(--input-border);
    border-radius: 24px;
    font-size: 15px;
    background-color: var(--input-bg);
    color: var(--text-primary);
    transition: border-color 0.2s, box-shadow 0.2s;
}

#messageInput:focus {
    outline: none;
    border-color: var(--input-focus);
    box-shadow: 0 0 0 2px rgba(26, 115, 232, 0.2);
}

#messageInput::placeholder {
    color: var(--text-tertiary);
}

#sendButton {
    padding: 12px 24px;
    background: var(--button-bg);
    color: var(--button-text);
    border: none;
    border-radius: 24px;
    font-size: 15px;
    font-weight: 500;
    cursor: pointer;
    transition: background-color 0.2s, box-shadow 0.2s;
    white-space: nowrap;
    writing-mode: horizontal-tb;
    text-orientation: mixed;
    flex-shrink: 0;
}

#sendButton:hover {
    background: var(--button-hover);
    box-shadow: var(--shadow-sm);
}

#sendButton:active {
    box-shadow: none;
}

@keyframes fadeIn {
    from {
        opacity: 0;
        transform: translateY(10px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

@keyframes slideIn {
    from {
        opacity: 0;
        transform: translateX(-10px);
    }
    to {
        opacity: 1;
        transform: translateX(0);
    }
}

.messages::-webkit-scrollbar {
    width: 8px;
}

.messages::-webkit-scrollbar-track {
    background: var(--bg-secondary);
    border-radius: 4px;
}

.messages::-webkit-scrollbar-thumb {
    background: var(--border-color);
    border-radius: 4px;
}

.messages::-webkit-scrollbar-thumb:hover {
    background: var(--text-tertiary);
}

.room-members-sidebar__content::-webkit-scrollbar {
    width: 6px;
}

.room-members-sidebar__content::-webkit-scrollbar-track {
    background: var(--bg-secondary);
    border-radius: 3px;
}

.room-members-sidebar__content::-webkit-scrollbar-thumb {
    background: var(--border-color);
    border-radius: 3px;
}

.room-members-sidebar__content::-webkit-scrollbar-thumb:hover {
    background: var(--text-tertiary);
}

.modal {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.5);
    display: flex;
    justify-content: center;
    align-items: center;
    z-index: 1000;
    animation: fadeIn 0.3s ease-in;
}

.modal.hidden {
    display: none;
}

.modal-content {
    background: var(--modal-bg);
    border-radius: 8px;
    padding: 32px;
    max-width: 400px;
    width: 90%;
    box-shadow: var(--shadow-lg);
    animation: slideUp 0.3s ease-out;
    border: 1px solid var(--border-color);
}

.modal-title {
    color: var(--modal-text);
    font-size: 20px;
    font-weight: 400;
    margin-bottom: 16px;
}

.modal-message {
    color: var(--modal-text);
    font-size: 15px;
    line-height: 1.6;
    margin-bottom: 24px;
}

.modal-button {
    background: var(--button-bg);
    color: var(--button-text);
    border: none;
    padding: 10px 24px;
    border-radius: 4px;
    cursor: pointer;
    font-size: 14px;
    font-weight: 500;
    float: right;
    transition: background-color 0.2s, box-shadow 0.2s;
}

.modal-button:hover {
    background: var(--button-hover);
    box-shadow: var(--shadow-sm);
}

.image-preview-modal {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    z-index: 10000;
    display: flex;
    align-items: center;
    justify-content: center;
}

.image-preview-modal.hidden {
    display: none;
}

.image-preview-modal-overlay {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.9);
    backdrop-filter: blur(4px);
}

.image-preview-modal-content {
    position: relative;
    max-width: 90vw;
    max-height: 90vh;
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 10001;
}

.image-preview-modal-content img {
    max-width: 100%;
    max-height: 90vh;
    object-fit: contain;
    border-radius: 8px;
    box-shadow: 0 8px 32px rgba(0, 0, 0, 0.5);
}

.image-preview-modal-close {
    position: absolute;
    top: 20px;
    right: 20px;
    width: 40px;
    height: 40px;
    border-radius: 50%;
    background: rgba(0, 0, 0, 0.6);
    border: none;
    color: white;
    font-size: 24px;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 10002;
    transition: opacity 0.3s ease, background 0.2s ease;
    opacity: 0;
}

.image-preview-modal:hover .image-preview-modal-close,
.image-preview-modal.show-ui .image-preview-modal-close {
    opacity: 1;
}

.image-preview-modal-close:hover {
    background: rgba(0, 0, 0, 0.8);
}

.image-preview-modal-nav {
    position: absolute;
    top: 50%;
    transform: translateY(-50%);
    width: 50px;
    height: 50px;
    border-radius: 50%;
    background: rgba(0, 0, 0, 0.6);
    border: none;
    color: white;
    font-size: 32px;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 10002;
    transition: opacity 0.3s ease, background 0.2s ease;
    line-height: 1;
    opacity: 0;
}

.image-preview-modal:hover .image-preview-modal-nav,
.image-preview-modal.show-ui .image-preview-modal-nav {
    opacity: 1;
}

.image-preview-modal-nav:hover {
    background: rgba(0, 0, 0, 0.8);
}

.image-preview-modal-prev {
    left: 20px;
}

.image-preview-modal-next {
    right: 20px;
}

.image-preview-modal-counter {
    position: absolute;
    bottom: 20px;
    left: 50%;
    transform: translateX(-50%);
    background: rgba(0, 0, 0, 0.6);
    color: white;
    padding: 8px 16px;
    border-radius: 20px;
    font-size: 14px;
    z-index: 10002;
    transition: opacity 0.3s ease;
    opacity: 0;
}

.image-preview-modal:hover .image-preview-modal-counter,
.image-preview-modal.show-ui .image-preview-modal-counter {
    opacity: 1;
}

@keyframes slideUp {
    from {
        opacity: 0;
        transform: translateY(20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

@media (max-width: 1024px) {
    .ad-sidebar {
        display: none;
    }
    
    .chat-content-wrapper {
        flex-direction: column;
    }
    
    .room-members-sidebar {
        width: 100%;
        border-left: none;
        border-top: 1px solid var(--border-color);
        max-height: 300px;
    }
}

@media (max-width: 768px) {
    body {
        padding: 16px;
    }

    .container {
        max-width: 100%;
    }

    .join-form {
        padding: 40px 32px;
        max-width: 100%;
    }

    .form-container h1 {
        font-size: 28px;
    }

    .chat-container {
        height: calc(100vh - 32px);
        min-height: 0;
        overflow: hidden;
    }

    .chat-header {
        padding: 14px 20px;
    }

    .chat-header h2 {
        font-size: 18px;
    }

    .messages {
        padding: 20px;
        min-height: 0;
    }

    .chat-input-container {
        padding: 14px 20px;
        border-top: none;
    }
    
    [data-device-type="mobile"] .chat-input-container {
        border-top: 1px solid var(--border-color);
    }
    
    [data-device-type="mobile"] .ad-bottom {
        display: none !important;
    }

    .ad-top,
    .ad-bottom {
        max-width: 100%;
        height: 60px;
    }
}

@media (max-width: 600px) {
    body {
        padding: 0;
        font-size: 14px;
    }

    [data-device-type="mobile"] body {
        padding: 0 !important;
    }

    .container {
        max-width: 100%;
        padding: 0;
    }

    .page-header {
        padding: 10px 12px;
        margin-bottom: 12px;
    }
    .site-logo {
        font-size: 22px;
        padding: 8px 10px;
    }
    .theme-toggle {
        padding: 8px 14px;
        font-size: 12px;
        border-radius: 20px;
    }

    .theme-text {
        font-size: 12px;
    }

    .ad-container {
        margin: 10px 0;
        border-radius: 4px;
    }

    .ad-top {
        height: 50px;
        margin: 10px auto 20px;
    }

    .ad-bottom {
        height: 50px;
        margin: 20px auto 10px;
    }

    .join-form {
        padding: 24px 20px;
        border-radius: 0;
        margin: 0;
        box-shadow: none;
        border: none;
        border-bottom: 1px solid var(--border-color);
    }

    .join-form.hidden {
        display: none !important;
    }

    .form-container h1 {
        font-size: 24px;
        margin-bottom: 24px;
    }

    .warning-box {
        padding: 12px;
        margin-bottom: 24px;
        font-size: 13px;
    }

    .warning-box strong {
        font-size: 13px;
    }

    .warning-box p {
        font-size: 12px;
    }

    .form-group {
        margin-bottom: 20px;
    }

    .form-group label {
        font-size: 13px;
        margin-bottom: 6px;
    }

    .form-group input {
        padding: 10px 14px;
        font-size: 16px;
        border-radius: 8px;
    }

    #joinButton {
        padding: 12px 20px;
        font-size: 15px;
        border-radius: 8px;
        margin-top: 4px;
    }

    .chat-container {
        height: 100vh;
        height: 100dvh;
        height: calc(var(--vh, 1vh) * 100);
        border-radius: 0;
        margin: 0;
        box-shadow: none;
        border: none;
        position: fixed;
        top: 0;
        left: 0;
        right: 0;
        bottom: 0;
        max-width: 100%;
        z-index: 100;
        min-height: 0;
        overflow: hidden;
    }

    [data-device-type="mobile"] .chat-container {
        height: 100vh;
        height: 100dvh;
        height: calc(var(--vh, 1vh) * 100);
        position: fixed;
        top: 0;
        left: 0;
        right: 0;
        bottom: 0;
        margin: 0;
        border-radius: 0;
        max-width: 100%;
        z-index: 100;
        min-height: 0;
        overflow: hidden;
    }
    
    [data-device-type="mobile"] .chat-container:not(.hidden) ~ .page-header,
    [data-device-type="mobile"] .chat-container:not(.hidden) ~ .tabs,
    [data-device-type="mobile"] .chat-container:not(.hidden) ~ .join-form,
    [data-device-type="mobile"] .chat-container:not(.hidden) ~ .active-rooms {
        display: none !important;
    }
    
    [data-device-type="mobile"] .chat-container:not(.hidden) ~ * {
        display: none !important;
    }
    
    [data-device-type="mobile"] .chat-container:not(.hidden) {
        display: flex !important;
    }

    .chat-header {
        padding: 12px 16px;
        border-radius: 0;
    }

    .chat-header h2 {
        font-size: 16px;
    }
    
    .room-members-sidebar-open {
        padding: 6px 10px;
        font-size: 14px;
        min-width: 36px;
        min-height: 36px;
    }
    
    .room-members-sidebar {
        width: 100%;
        max-height: 200px;
    }
    
    .room-members-sidebar__header {
        padding: 12px;
    }
    
    .room-members-sidebar__title {
        font-size: 14px;
    }
    
    .room-members-sidebar__content {
        padding: 8px;
    }
    
    .room-members-sidebar__item {
        padding: 8px 10px;
        font-size: 13px;
    }

    .user-icon-preview-container {
        width: 48px;
        height: 48px;
    }

    .user-icon-placeholder {
        font-size: 24px;
    }

    .user-icon-upload-button,
    .user-icon-remove-button {
        padding: 6px 12px;
        font-size: 13px;
    }

    .leave-button {
        padding: 6px 12px;
        font-size: 13px;
        border-radius: 6px;
    }

    .messages {
        padding: 16px;
        min-height: 0;
    }

    .message {
        margin-bottom: 12px;
    }

    .message-bubble {
        max-width: 100%;
        padding: 0;
        font-size: 14px;
        border-radius: 0;
        box-shadow: none;
        background: transparent;
    }

    .message-name {
        font-size: 11px;
        margin-bottom: 3px;
        gap: 4px;
    }

    .message-mute-button {
        opacity: 0.5;
        min-width: 28px;
        min-height: 28px;
        padding: 4px;
        font-size: 14px;
        margin-left: 2px;
    }

    .message-mute-button:active {
        opacity: 1;
    }

    .message-icon {
        width: 32px;
        height: 32px;
    }

    .message-time {
        font-size: 10px;
    }

    .message.system {
        font-size: 12px;
        padding: 6px;
        margin: 6px 0;
    }

    .chat-input-container {
        padding: 12px 16px;
        gap: 8px;
    }

    #messageInput {
        padding: 10px 14px;
        font-size: 16px;
        border-radius: 20px;
    }

    #sendButton {
        padding: 10px 20px;
        font-size: 14px;
        border-radius: 20px;
        min-width: 60px;
    }

    .stats-bar {
        text-align: center;
        margin: 20px 0 30px;
        font-size: 13px;
    }

    .tabs {
        margin: 12px 12px 0;
    }

    .tab-button {
        flex: 1;
        text-align: center;
    }

    .active-rooms {
        margin: 16px 12px 0;
        padding: 14px;
    }

    .active-rooms__header {
        flex-direction: column;
        align-items: flex-start;
        gap: 4px;
    }

    .active-rooms__list {
        grid-template-columns: 1fr;
    }

    .active-rooms__hint {
        margin-bottom: 8px;
    }

    .modal {
        padding: 16px;
    }

    .modal-content {
        padding: 20px 16px;
        max-width: 100%;
        width: calc(100% - 32px);
        border-radius: 12px;
    }

    .modal-title {
        font-size: 18px;
        margin-bottom: 12px;
    }

    .modal-message {
        font-size: 14px;
        margin-bottom: 20px;
    }

    .modal-button {
        padding: 10px 20px;
        font-size: 14px;
    }
}

@media (max-width: 360px) {
    .theme-toggle {
        top: 8px;
        right: 8px;
        padding: 6px 12px;
        font-size: 11px;
    }

    .theme-text {
        font-size: 11px;
    }

    .join-form {
        padding: 20px 16px;
    }

    .form-container h1 {
        font-size: 22px;
        margin-bottom: 20px;
    }

    .form-group input {
        padding: 8px 12px;
    }

    #joinButton {
        padding: 10px 16px;
        font-size: 14px;
    }

    .chat-header {
        padding: 10px 12px;
    }

    .chat-header h2 {
        font-size: 15px;
    }

    .messages {
        padding: 12px;
        min-height: 0;
    }
    
    .message-bubble {
        max-width: 100%;
        padding: 0;
        font-size: 13px;
        border-radius: 0;
        box-shadow: none;
        background: transparent;
    }

    .chat-input-container {
        padding: 10px 12px;
    }
    
    .input-row {
        gap: 6px;
    }
    
    .image-button {
        padding: 8px 10px;
        font-size: 16px;
    }
    
    .image-preview-item {
        max-width: 100px;
    }
    
    .image-preview-img {
        max-height: 100px;
    }
    
    .message-image {
        max-width: 150px;
        max-height: 150px;
    }
    
    .image-preview-modal-content {
        max-width: 95vw;
        max-height: 95vh;
    }
    
    .image-preview-modal-close {
        top: 10px;
        right: 10px;
        width: 36px;
        height: 36px;
        font-size: 20px;
    }
    
    .image-preview-modal-nav {
        width: 40px;
        height: 40px;
        font-size: 28px;
    }
    
    .image-preview-modal-prev {
        left: 10px;
    }
    
    .image-preview-modal-next {
        right: 10px;
    }
    
    .image-preview-modal-counter {
        bottom: 10px;
        font-size: 12px;
        padding: 6px 12px;
    }
    
    .image-preview-modal.show-ui .image-preview-modal-close,
    .image-preview-modal.show-ui .image-preview-modal-nav,
    .image-preview-modal.show-ui .image-preview-modal-counter {
        opacity: 1;
    }

    #messageInput {
        padding: 8px 12px;
        font-size: 16px;
    }

    #sendButton {
        padding: 8px 16px;
        font-size: 13px;
        min-width: 60px;
        white-space: nowrap;
    }

    .ad-top,
    .ad-bottom {
        height: 40px;
    }
}

@media (hover: none) and (pointer: coarse) {
    button,
    .theme-toggle,
    .leave-button,
    #joinButton,
    #sendButton,
    .modal-button {
        min-height: 44px;
        min-width: 44px;
    }

    .theme-toggle:hover,
    #joinButton:hover,
    #sendButton:hover,
    .leave-button:hover,
    .modal-button:hover {
        transform: none;
    }
    
    .image-preview-modal-close,
    .image-preview-modal-nav,
    .image-preview-modal-counter {
        opacity: 1;
    }

    .theme-toggle:active,
    #joinButton:active,
    #sendButton:active,
    .leave-button:active,
    .modal-button:active {
        opacity: 0.8;
        transform: scale(0.98);
    }

    .messages {
        -webkit-overflow-scrolling: touch;
        overscroll-behavior: contain;
    }
}

@media (max-width: 600px) and (orientation: landscape) {
    .chat-container {
        height: 100vh;
        height: 100dvh;
        min-height: 0;
        overflow: hidden;
    }

    .chat-header {
        padding: 8px 16px;
    }

    .messages {
        padding: 12px;
        min-height: 0;
    }

    .chat-input-container {
        padding: 10px 16px;
    }

    .ad-top,
    .ad-bottom {
        height: 40px;
    }
}

/* ============================================================
   入力中インジケーター (Typing Indicator)
   ============================================================ */
.typing-indicator {
    display: flex;
    align-items: center;
    gap: 7px;
    padding: 4px 24px 5px;
    font-size: 13px;
    color: var(--text-secondary);
    font-style: italic;
    flex-shrink: 0;
    background: var(--bg-primary);
    min-height: 22px;
}

.typing-indicator.hidden {
    display: none;
}

.typing-dots {
    display: inline-flex;
    align-items: center;
    gap: 3px;
    flex-shrink: 0;
}

.typing-dots span {
    width: 5px;
    height: 5px;
    border-radius: 50%;
    background: var(--text-tertiary);
    animation: typingBounce 1.4s infinite ease-in-out both;
    display: inline-block;
}

.typing-dots span:nth-child(1) { animation-delay: -0.32s; }
.typing-dots span:nth-child(2) { animation-delay: -0.16s; }
.typing-dots span:nth-child(3) { animation-delay: 0s; }

@keyframes typingBounce {
    0%, 80%, 100% { transform: scale(0.7); opacity: 0.4; }
    40% { transform: scale(1.15); opacity: 1; }
}

@media (max-width: 600px) {
    .typing-indicator {
        padding: 3px 16px 4px;
        font-size: 12px;
    }
}

/* ============================================================
   返信プレビュー (Reply Preview bar above input)
   ============================================================ */
.reply-preview {
    display: flex;
    align-items: center;
    gap: 10px;
    padding: 7px 12px;
    background: var(--bg-secondary);
    border-left: 3px solid var(--accent-color);
    border-radius: 6px;
}

.reply-preview.hidden {
    display: none;
}

.reply-preview__content {
    flex: 1;
    min-width: 0;
    overflow: hidden;
}

.reply-preview__name {
    font-size: 12px;
    font-weight: 600;
    color: var(--accent-color);
    display: block;
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
}

.reply-preview__message {
    font-size: 12px;
    color: var(--text-secondary);
    display: block;
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
}

.reply-preview__cancel {
    background: transparent;
    border: none;
    color: var(--text-secondary);
    font-size: 20px;
    cursor: pointer;
    padding: 0 4px;
    line-height: 1;
    flex-shrink: 0;
    border-radius: 4px;
    transition: background 0.15s, color 0.15s;
    -webkit-tap-highlight-color: transparent;
}

.reply-preview__cancel:hover {
    background: var(--bg-tertiary);
    color: var(--text-primary);
}

/* ============================================================
   メッセージ内 返信引用ブロック (Reply quote inside message)
   ============================================================ */
.message-reply-quote {
    display: flex;
    flex-direction: column;
    margin-bottom: 5px;
    padding: 5px 10px;
    background: var(--bg-secondary);
    border-left: 3px solid var(--accent-color);
    border-radius: 4px;
    max-width: min(420px, 85vw);
    cursor: pointer;
    transition: background 0.15s;
    overflow: hidden;
}

.message-reply-quote:hover {
    background: var(--bg-tertiary);
}

.message-reply-quote__name {
    font-size: 12px;
    font-weight: 600;
    color: var(--accent-color);
    margin-bottom: 2px;
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
}

.message-reply-quote__text {
    font-size: 12px;
    color: var(--text-secondary);
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
}

/* ============================================================
   メッセージアクションボタン (Discord-style hover toolbar)
   ============================================================ */

/* メッセージにはrelativeが必要 */
.message.chat {
    position: relative;
}

.message-actions {
    position: absolute;
    top: 0;
    right: 0;
    display: flex;
    flex-direction: row;
    gap: 2px;
    align-items: center;
    opacity: 0;
    pointer-events: none;
    /* フェードアウトに少し遅延を持たせることで、ボタンへカーソルを移動しやすくする */
    transition: opacity 0.15s ease 0.15s;
    background: var(--modal-bg);
    border: 1px solid var(--border-color);
    border-radius: 8px;
    padding: 3px 5px;
    box-shadow: var(--shadow-sm);
    z-index: 10;
    transform: translateY(-30%);
}

/* メッセージ上にホバー、またはボタン自体にホバーで表示維持 */
.message:hover .message-actions,
.message-actions:hover {
    opacity: 1;
    pointer-events: auto;
    transition-delay: 0s;
}

/* モバイルタッチデバイス：常時非表示（長押しで出す） */
/* デスクトップ型タッチデバイス（Chromebookなど）はhoverで表示するため除外 */
[data-touch="true"][data-device-type="mobile"] .message-actions {
    display: none;
}

.message-action-btn {
    background: transparent;
    border: none;
    border-radius: 6px;
    padding: 4px 6px;
    cursor: pointer;
    font-size: 16px;
    color: var(--text-secondary);
    transition: background 0.12s ease, color 0.12s ease, transform 0.1s ease;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    min-height: 28px;
    min-width: 28px;
    line-height: 1;
    -webkit-tap-highlight-color: transparent;
    white-space: nowrap;
}

.message-action-btn:hover {
    background: var(--bg-tertiary);
    color: var(--text-primary);
    transform: scale(1.15);
}

.message-action-btn:active {
    transform: scale(0.95);
}

/* ============================================================
   メッセージリアクション (Reaction bar below message)
   ============================================================ */
.message-reactions {
    display: flex;
    flex-wrap: wrap;
    gap: 4px;
    margin-top: 5px;
}

.message-reaction-btn {
    display: inline-flex;
    align-items: center;
    gap: 4px;
    padding: 3px 8px;
    background: var(--bg-secondary);
    border: 1.5px solid var(--border-color);
    border-radius: 12px;
    cursor: pointer;
    font-size: 14px;
    transition: all 0.15s ease;
    -webkit-tap-highlight-color: transparent;
    line-height: 1;
}

.message-reaction-btn:hover {
    background: var(--bg-tertiary);
    box-shadow: var(--shadow-sm);
}

.message-reaction-btn.own {
    background: rgba(26, 115, 232, 0.1);
    border-color: var(--accent-color);
}

[data-theme="dark"] .message-reaction-btn.own {
    background: rgba(138, 180, 248, 0.15);
    border-color: var(--accent-color);
}

.message-reaction-btn:active {
    transform: scale(0.93);
}

.reaction-emoji {
    font-size: 15px;
    line-height: 1;
    display: inline-block;
}

.reaction-count {
    font-size: 12px;
    font-weight: 600;
    color: var(--text-secondary);
    line-height: 1;
    min-width: 10px;
}

.message-reaction-btn.own .reaction-count {
    color: var(--accent-color);
}

/* ============================================================
   リアクションピッカー (Reaction picker popup)
   ============================================================ */
.reaction-picker {
    position: fixed;
    background: var(--modal-bg);
    border: 1px solid var(--border-color);
    border-radius: 28px;
    box-shadow: var(--shadow-lg);
    padding: 6px 10px;
    display: flex;
    gap: 2px;
    align-items: center;
    z-index: 9500;
    animation: reactionPickerIn 0.15s ease-out;
}

.reaction-picker.hidden {
    display: none;
}

@keyframes reactionPickerIn {
    from { opacity: 0; transform: scale(0.8) translateY(6px); }
    to   { opacity: 1; transform: scale(1) translateY(0); }
}

.reaction-picker__emoji {
    background: transparent;
    border: none;
    font-size: 22px;
    cursor: pointer;
    padding: 5px 6px;
    border-radius: 8px;
    transition: transform 0.12s ease, background 0.12s ease;
    line-height: 1;
    -webkit-tap-highlight-color: transparent;
    display: inline-block;
}

.reaction-picker__emoji:hover {
    background: var(--bg-tertiary);
    transform: scale(1.3);
}

.reaction-picker__emoji:active {
    transform: scale(1.1);
}

[data-touch="true"] .reaction-picker__emoji {
    font-size: 24px;
    padding: 7px 8px;
    min-width: 44px;
    min-height: 44px;
    display: inline-flex;
    align-items: center;
    justify-content: center;
}

[data-device-type="mobile"] .reaction-picker {
    border-radius: 32px;
    padding: 8px 12px;
}

/* ============================================================
   スマホ用メッセージメニュー（長押し）
   ============================================================ */
.mobile-message-menu {
    position: fixed;
    left: 50%;
    bottom: max(env(safe-area-inset-bottom, 0px) + 16px, 80px);
    transform: translateX(-50%);
    background: var(--modal-bg);
    border: 1px solid var(--border-color);
    border-radius: 20px;
    box-shadow: var(--shadow-lg);
    padding: 10px 12px 8px;
    display: flex;
    flex-direction: column;
    gap: 6px;
    z-index: 9600;
    min-width: 300px;
    max-width: calc(100vw - 32px);
    animation: mobileMenuIn 0.18s ease-out;
}

@keyframes mobileMenuIn {
    from { opacity: 0; transform: translateX(-50%) translateY(16px) scale(0.95); }
    to   { opacity: 1; transform: translateX(-50%) translateY(0) scale(1); }
}

.mobile-message-menu__reactions {
    display: flex;
    justify-content: space-around;
    gap: 4px;
    padding-bottom: 8px;
    border-bottom: 1px solid var(--border-color);
}

.mobile-message-menu__emoji {
    background: transparent;
    border: none;
    font-size: 28px;
    cursor: pointer;
    padding: 4px;
    border-radius: 8px;
    transition: transform 0.1s ease, background 0.1s ease;
    min-width: 44px;
    min-height: 44px;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    -webkit-tap-highlight-color: transparent;
}

.mobile-message-menu__emoji:active {
    transform: scale(1.3);
    background: var(--bg-tertiary);
}

.mobile-message-menu__action {
    background: transparent;
    border: none;
    color: var(--text-primary);
    font-size: 16px;
    text-align: left;
    padding: 10px 8px;
    border-radius: 10px;
    cursor: pointer;
    width: 100%;
    -webkit-tap-highlight-color: transparent;
    transition: background 0.1s ease;
}

.mobile-message-menu__action:active {
    background: var(--bg-tertiary);
}