/* --- CSS Variables --- */
:root {
    --bg-primary: #18181b;
    --bg-secondary: #2a2a2e;
    --bg-tertiary: #3a3a3e;
    --text-primary: #efeff1;
    --text-secondary: #adadb8;
    --accent-primary: #9147ff;
    --accent-danger: #e91916;

    --font-family-base: 'Noto Sans JP', sans-serif;
    --font-family-chat: 'Noto Sans JP', sans-serif;
    --font-weight-chat: 400;
    --font-size-base: 14px;
    --line-height-chat: 1.5;
    --chat-padding: 20px;
    --text-outline-style: none;
    --color-username: #ffffff;
    --color-message: #efefef;

    --sidebar-width: 300px;
    --sidebar-right-width: 350px;

    --theme-accent-rgb: 145, 71, 255; /* #9147ff */
    --theme-bg-rgb: 24, 24, 27;       /* #18181b */
    --theme-accent-opacity: 1;
    --theme-bg-opacity: 1;
}

/* --- Base & Reset --- */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

html, body {
    height: 100%;
    overflow: hidden;
    font-family: var(--font-family-base);
    background-color: #18181b00;
    color: var(--text-primary);
}

ul {
    list-style: none;
}

/* --- Layout --- */
#app-container {
    display: grid;
    grid-template-columns: var(--sidebar-width) 1fr var(--sidebar-right-width);
    height: 100vh;
    transition: grid-template-columns 0.3s ease;
}

.sidebar {
    background-color: var(--bg-secondary);
    display: flex;
    flex-direction: column;
    transition: width 0.3s ease, opacity 0.3s ease;
    overflow: hidden;
    position: relative;
}

#main-view {
    display: flex;
    flex-direction: column;
    height: 100%;
    background-color: #18181b00;
    overflow: hidden;
}

/* --- Sidebar Toggling --- */
#app-container.left-closed {
    grid-template-columns: 0 1fr var(--sidebar-right-width);
}
#app-container.right-closed {
    grid-template-columns: var(--sidebar-width) 1fr 0;
}
#app-container.left-closed.right-closed {
    grid-template-columns: 0 1fr 0;
}

/* --- Headers --- */
.sidebar-header, .main-header {
    display: flex;
    align-items: center;
    padding: 12px 16px;
    background-color: var(--bg-tertiary);
    flex-shrink: 0;
}

.main-header {
    justify-content: space-between;
}

.sidebar-header h2, .main-header h1 {
    font-size: 1.1rem;
    margin: 0;
    flex-grow: 1;
    text-align: center;
}

#sidebar-right .sidebar-header {
    justify-content: flex-end;
}

/* --- Sidebar Content --- */
.sidebar-content {
    padding: 16px;
    overflow-y: auto;
    flex-grow: 1;
}

/* --- Main Chat View --- */
#chat-container {
    flex-grow: 1;
    overflow-y: auto;
    min-height: 0;
    padding: 10px var(--chat-padding);
    font-size: var(--font-size-base);
    font-family: var(--font-family-chat);
    font-weight: var(--font-weight-chat);
    word-wrap: break-word;

    /* スクロールバーを非表示にする */
    -ms-overflow-style: none;  /* IE and Edge */
    scrollbar-width: none;  /* Firefox */
}

/* スクロールバーを非表示にする (Chrome, Safari, Opera) */
#chat-container::-webkit-scrollbar {
    display: none;
}

/* --- Sidebar & Modal Scrollbar --- */
.sidebar-content::-webkit-scrollbar,
#ng-user-list::-webkit-scrollbar,
.modal-content::-webkit-scrollbar {
    width: 8px;
}
.sidebar-content::-webkit-scrollbar-track,
#ng-user-list::-webkit-scrollbar-track,
.modal-content::-webkit-scrollbar-track {
    background: var(--bg-primary);
}
.sidebar-content::-webkit-scrollbar-thumb,
#ng-user-list::-webkit-scrollbar-thumb,
.modal-content::-webkit-scrollbar-thumb {
    background-color: var(--bg-tertiary);
    border-radius: 4px;
}
.sidebar-content::-webkit-scrollbar-thumb:hover,
#ng-user-list::-webkit-scrollbar-thumb:hover,
.modal-content::-webkit-scrollbar-thumb:hover {
    background-color: var(--text-secondary);
}

/* --- Buttons --- */
.btn, .icon-btn {
    background-color: var(--accent-primary);
    color: var(--text-primary);
    border: none;
    border-radius: 4px;
    cursor: pointer;
    transition: background-color 0.2s ease, filter 0.2s ease;
    font-family: inherit;
}

.btn {
    padding: 8px 12px;
    font-size: 0.9rem;
}

.icon-btn {
    background: none;
    font-size: 1.2rem;
    padding: 4px;
    width: 32px;
    height: 32px;
    line-height: 1;
}

.btn:hover {
    filter: brightness(0.9);
}

.icon-btn:hover {
    background-color: rgba(255, 255, 255, 0.1);
}

.btn.full-width {
    width: 100%;
    display: block;
}

.btn.btn-danger {
    background-color: var(--accent-danger);
}
.btn.btn-danger:hover {
    filter: brightness(0.9);
}

/* --- Forms & Inputs --- */
.input-group {
    display: flex;
    margin-bottom: 16px;
}

.input-group input {
    flex-grow: 1;
    min-width: 0;
}

input[type="text"], select {
    background-color: var(--bg-primary);
    border: 1px solid var(--bg-tertiary);
    color: var(--text-primary);
    padding: 8px;
    border-radius: 4px;
    font-size: 0.9rem;
}

.input-group input {
    border-top-right-radius: 0;
    border-bottom-right-radius: 0;
}

.input-group button {
    border-top-left-radius: 0;
    border-bottom-left-radius: 0;
}

/* --- Channel List --- */
#channel-list {
    display: flex;
    flex-direction: column;
    gap: 8px;
}

/* (Placeholder for items added by JS) */
.channel-item {
    display: flex;
    align-items: center;
    gap: 8px;
    padding: 8px;
    background-color: var(--bg-tertiary);
    border-radius: 4px;
}

.channel-status-icon {
    width: 16px;
    text-align: center;
    font-size: 0.9em;
}
.channel-status-icon[data-status="connected"] { color: #2f9e44; } /* green */
.channel-status-icon[data-status="error"] { color: var(--accent-danger); } /* red */
.channel-status-icon[data-status="disconnected"] { color: var(--text-secondary); } /* gray */
.channel-status-icon[data-status="connecting"] { color: var(--accent-primary); } /* purple */

.channel-name {
    flex-grow: 1;
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
}

/* --- NG User List --- */
#ng-user-list {
    display: flex;
    flex-direction: column;
    gap: 8px;
    max-height: 150px; /* リストが長くなりすぎないように */
    overflow-y: auto;
}

.ng-user-item {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 8px;
    background-color: var(--bg-tertiary);
    border-radius: 4px;
    font-size: 0.9rem;
}

/* --- Settings Panel --- */
.setting-group {
    margin-bottom: 24px;
}

.setting-group h3 {
    font-size: 1rem;
    color: var(--text-secondary);
    margin-bottom: 12px;
    border-bottom: 1px solid var(--bg-tertiary);
    padding-bottom: 8px;
}

.setting-group label {
    display: block;
    margin-top: 15px;
    margin-bottom: 5px;
    font-size: 0.9rem;
}

.setting-group select {
    width: 100%;
    margin-bottom: 12px;
}

/* --- Range Slider --- */
input[type="range"] {
    -webkit-appearance: none;
    appearance: none;
    width: 100%;
    height: 6px;
    background: var(--bg-primary);
    border-radius: 3px;
    outline: none;
    margin: 8px 0;
    cursor: pointer;
}

input[type="range"]::-webkit-slider-thumb {
    -webkit-appearance: none;
    appearance: none;
    width: 18px;
    height: 18px;
    background: var(--accent-primary);
    border-radius: 50%;
    transition: filter 0.2s;
}

input[type="range"]::-moz-range-thumb {
    width: 18px;
    height: 18px;
    background: var(--accent-primary);
    border-radius: 50%;
    transition: filter 0.2s;
}

input[type="range"]:hover::-webkit-slider-thumb,
input[type="range"]:hover::-moz-range-thumb {
    filter: brightness(0.9);
}

.color-row {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 8px;
}

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

input[type="color"] {
    -webkit-appearance: none;
    -moz-appearance: none;
    appearance: none;
    width: 44px;
    height: 28px;
    background-color: transparent;
    border: 1px solid var(--bg-tertiary);
    border-radius: 4px;
    cursor: pointer;
}
input[type="color"]::-webkit-color-swatch {
    border-radius: 3px;
    border: none;
}
input[type="color"]::-moz-color-swatch {
    border-radius: 3px;
    border: none;
}

.bg-controls {
    display: flex;
    gap: 10px;
    align-items: center;
}
.bg-controls label {
    margin-top: 0;
    margin-bottom: 0;
    margin-right: 5px;
}
.bg-controls .btn {
    flex-grow: 1;
}

.setting-group .btn {
    margin-bottom: 8px;
}

/* --- Checkbox Row --- */
.checkbox-row {
    display: flex;
    align-items: center;
    margin-top: 15px;
    margin-bottom: 12px;
}
.checkbox-row input[type="checkbox"] {
    margin-right: 8px;
    cursor: pointer;
    width: 16px;
    height: 16px;
}
.checkbox-row label {
    margin-top: 0;
    margin-bottom: 0;
    cursor: pointer;
    user-select: none;
}

/* --- Chat Message (Placeholder) --- */
.chat-message {
    margin-bottom: 4px;
    line-height: var(--line-height-chat);
    word-break: break-word;
    width: var(--chat-message-width);
    max-width: 100%;
}
.chat-message .username {
    font-weight: bold;
    color: var(--color-username);
}
.chat-message .message-body {
    color: var(--color-message);
    padding-left: 6px;
}
.chat-message .emote {
    height: 1.5em;
    vertical-align: middle;
    margin: -0.25em 0;
}

/* --- Resizer --- */
.resizer {
    position: absolute;
    top: 0;
    bottom: 0;
    width: 5px;
    cursor: col-resize;
    z-index: 100;
    transition: background-color 0.2s;
}
.resizer:hover, .resizer.resizing {
    background-color: var(--accent-primary);
}
#resizer-right {
    left: 0;
}
#resizer-left {
    right: 0;
}

/* --- Chat Themes --- */

/* Default Theme */
#chat-container[data-chat-theme="default"] .chat-message {
    padding: 2px 0;
    border-bottom: 1px solid rgba(255, 255, 255, 0.05);
}

/* Bubble Theme */
#chat-container[data-chat-theme="bubble"] .chat-message {
    position: relative;
    background-color: rgba(var(--theme-bg-rgb), var(--theme-bg-opacity));
    border-radius: 0 12px 12px 12px;
    padding: 10px 14px;
    margin-bottom: 12px;
}
#chat-container[data-chat-theme="bubble"] .chat-message::before {
    content: "";
    position: absolute;
    top: 0;
    left: -8px;
    border-top: 10px solid rgba(var(--theme-bg-rgb), var(--theme-bg-opacity));
    border-left: 8px solid transparent;
}
#chat-container[data-chat-theme="bubble"] .username {
    display: block;
    font-size: 0.85em;
    margin-bottom: 2px;
    opacity: 0.9;
}

/* Card Theme */
#chat-container[data-chat-theme="card"] .chat-message {
    background-color: rgba(var(--theme-bg-rgb), var(--theme-bg-opacity));
    border: 1px solid rgba(var(--theme-accent-rgb), var(--theme-accent-opacity));
    border-radius: 6px;
    padding: 12px;
    margin-bottom: 10px;
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.25);
}

/* Neon Theme */
#chat-container[data-chat-theme="neon"] .chat-message {
    background-color: rgba(var(--theme-bg-rgb), var(--theme-bg-opacity));
    border: 1px solid rgba(var(--theme-accent-rgb), var(--theme-accent-opacity));
    border-radius: 4px;
    padding: 10px;
    margin-bottom: 10px;
    box-shadow: 0 0 5px rgba(var(--theme-accent-rgb), var(--theme-accent-opacity)), inset 0 0 2px rgba(var(--theme-accent-rgb), var(--theme-accent-opacity));
}

/* Cute Theme */
#chat-container[data-chat-theme="cute"] .chat-message {
    background-color: rgba(var(--theme-bg-rgb), var(--theme-bg-opacity));
    border: 2px solid rgba(var(--theme-accent-rgb), var(--theme-accent-opacity));
    border-radius: 16px;
    padding: 10px 14px;
    margin-bottom: 12px;
    box-shadow: 0 2px 4px rgba(var(--theme-accent-rgb), 0.2);
}
#chat-container[data-chat-theme="cute"] .username {
    display: inline-block;
    background-color: #fff;
    padding: 2px 8px;
    border-radius: 12px;
    margin-right: 6px;
    font-weight: bold;
    border: 1px solid rgba(var(--theme-accent-rgb), var(--theme-accent-opacity));
}

/* Gaming Theme */
#chat-container[data-chat-theme="gaming"] .chat-message {
    background: linear-gradient(90deg, rgba(var(--theme-bg-rgb), var(--theme-bg-opacity)) 0%, rgba(var(--theme-bg-rgb), calc(var(--theme-bg-opacity) * 0.7)) 100%);
    border-left: 4px solid rgba(var(--theme-accent-rgb), var(--theme-accent-opacity));
    padding: 8px 12px;
    margin-bottom: 8px;
    clip-path: polygon(0 0, 100% 0, 100% 85%, 98% 100%, 0 100%); /* 右下をカット */
}
#chat-container[data-chat-theme="gaming"] .username {
    text-shadow: 0 0 8px;
    font-style: italic;
    margin-right: 8px;
}
#chat-container[data-chat-theme="gaming"] .message-body {
    text-shadow: 0 0 2px rgba(0, 0, 0, 0.8);
}

/* Terminal Theme */
#chat-container[data-chat-theme="terminal"] .chat-message {
    background-color: rgba(var(--theme-bg-rgb), var(--theme-bg-opacity));
    border: 1px solid rgba(var(--theme-accent-rgb), var(--theme-accent-opacity));
    padding: 6px 10px;
    margin-bottom: 6px;
    font-family: 'Roboto Mono', monospace; /* 等幅フォント強制 */
    box-shadow: 0 0 4px rgba(var(--theme-accent-rgb), 0.25);
}
#chat-container[data-chat-theme="terminal"] .username::before {
    content: "> ";
    color: inherit;
    margin-right: 4px;
}

/* Retro Theme */
#chat-container[data-chat-theme="retro"] .chat-message {
    background-color: rgba(var(--theme-bg-rgb), var(--theme-bg-opacity));
    border: 2px solid rgba(var(--theme-accent-rgb), var(--theme-accent-opacity));
    box-shadow: 4px 4px 0 rgba(var(--theme-accent-rgb), var(--theme-accent-opacity));
    border-radius: 0;
    padding: 10px;
    margin-bottom: 12px;
    image-rendering: pixelated;
}

/* Glass Theme */
#chat-container[data-chat-theme="glass"] .chat-message {
    background-color: rgba(var(--theme-bg-rgb), var(--theme-bg-opacity));
    backdrop-filter: blur(4px);
    -webkit-backdrop-filter: blur(4px);
    border: 1px solid rgba(255, 255, 255, 0.3);
    border-radius: 12px;
    padding: 10px 14px;
    margin-bottom: 10px;
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
}

/* Comic Theme */
#chat-container[data-chat-theme="comic"] .chat-message {
    background-color: rgba(var(--theme-bg-rgb), var(--theme-bg-opacity));
    border: 2px solid rgba(var(--theme-accent-rgb), var(--theme-accent-opacity));
    border-radius: 255px 15px 225px 15px / 15px 225px 15px 255px;
    padding: 12px 16px;
    margin-bottom: 12px;
    box-shadow: 2px 2px 0 rgba(0, 0, 0, 0.1);
}
#chat-container[data-chat-theme="comic"] .username {
    text-decoration: underline;
    text-decoration-color: rgba(var(--theme-accent-rgb), 0.5);
    text-decoration-thickness: 2px;
}

/* Cyber Theme */
#chat-container[data-chat-theme="cyber"] .chat-message {
    background-color: rgba(var(--theme-bg-rgb), var(--theme-bg-opacity));
    border: 1px solid rgba(var(--theme-accent-rgb), var(--theme-accent-opacity));
    border-left: 6px solid rgba(var(--theme-accent-rgb), var(--theme-accent-opacity));
    padding: 8px 12px;
    margin-bottom: 8px;
    clip-path: polygon(0 0, 100% 0, 100% 100%, 10px 100%, 0 calc(100% - 10px)); /* 左下をカット */
}
#chat-container[data-chat-theme="cyber"] .username {
    text-transform: uppercase;
    letter-spacing: 1px;
    font-weight: 800;
    margin-right: 8px;
}

/* Coffee Theme */
#chat-container[data-chat-theme="coffee"] .chat-message {
    background-color: rgba(var(--theme-bg-rgb), var(--theme-bg-opacity));
    border: 2px dashed rgba(var(--theme-accent-rgb), var(--theme-accent-opacity));
    border-radius: 15px;
    padding: 10px 14px;
    margin-bottom: 12px;
}
#chat-container[data-chat-theme="coffee"] .username {
    font-weight: bold;
    border-bottom: 1px dotted rgba(var(--theme-accent-rgb), var(--theme-accent-opacity));
    margin-right: 6px;
}

/* Navy Theme */
#chat-container[data-chat-theme="navy"] .chat-message {
    background: linear-gradient(180deg, rgba(var(--theme-bg-rgb), var(--theme-bg-opacity)) 0%, rgba(var(--theme-bg-rgb), calc(var(--theme-bg-opacity) * 0.8)) 100%);
    border-top: 2px solid rgba(var(--theme-accent-rgb), var(--theme-accent-opacity));
    border-bottom: 1px solid rgba(255, 255, 255, 0.05);
    padding: 10px 12px;
    margin-bottom: 8px;
}
#chat-container[data-chat-theme="navy"] .username {
    background-color: rgba(var(--theme-accent-rgb), 0.15);
    padding: 2px 6px;
    border-radius: 4px;
    margin-right: 8px;
    font-weight: bold;
}

/* Forest Theme */
#chat-container[data-chat-theme="forest"] .chat-message {
    background-color: rgba(var(--theme-bg-rgb), var(--theme-bg-opacity));
    border-left: 4px solid rgba(var(--theme-accent-rgb), var(--theme-accent-opacity));
    border-radius: 4px;
    padding: 8px 12px;
    margin-bottom: 8px;
}
#chat-container[data-chat-theme="forest"] .username {
    font-weight: bold;
    margin-right: 6px;
}

/* Sunset Theme */
#chat-container[data-chat-theme="sunset"] .chat-message {
    background: linear-gradient(135deg, rgba(var(--theme-bg-rgb), var(--theme-bg-opacity)) 0%, rgba(var(--theme-bg-rgb), calc(var(--theme-bg-opacity) * 0.6)) 100%);
    border-radius: 15px 0 15px 0;
    padding: 10px 14px;
    margin-bottom: 10px;
    border: 1px solid rgba(255, 255, 255, 0.1);
}

/* Monochrome Theme */
#chat-container[data-chat-theme="monochrome"] .chat-message {
    background-color: rgba(var(--theme-bg-rgb), var(--theme-bg-opacity));
    border: 1px solid rgba(var(--theme-accent-rgb), var(--theme-accent-opacity));
    padding: 10px;
    margin-bottom: 10px;
}
#chat-container[data-chat-theme="monochrome"] .username {
    background-color: rgba(var(--theme-accent-rgb), var(--theme-accent-opacity));
    color: rgba(var(--theme-bg-rgb), 1); /* 背景色を文字色として使用して反転効果 */
    padding: 2px 6px;
    margin-right: 6px;
    font-weight: bold;
}

/* Vaporwave Theme */
#chat-container[data-chat-theme="vaporwave"] .chat-message {
    background: linear-gradient(90deg, rgba(var(--theme-bg-rgb), var(--theme-bg-opacity)) 0%, rgba(var(--theme-bg-rgb), calc(var(--theme-bg-opacity) * 0.8)) 100%);
    border: 2px solid rgba(var(--theme-accent-rgb), var(--theme-accent-opacity));
    border-radius: 0;
    padding: 10px 14px;
    margin-bottom: 12px;
    box-shadow: 4px 4px 0 rgba(0, 255, 255, 0.5);
}
#chat-container[data-chat-theme="vaporwave"] .username {
    text-shadow: 2px 2px 0 rgba(255, 0, 255, 0.5);
    font-weight: bold;
    margin-right: 6px;
}

/* Clay Theme */
#chat-container[data-chat-theme="clay"] .chat-message {
    background-color: rgba(var(--theme-bg-rgb), var(--theme-bg-opacity));
    border-radius: 20px;
    padding: 12px 16px;
    margin-bottom: 12px;
    box-shadow: inset 2px 2px 5px rgba(255, 255, 255, 0.1), inset -2px -2px 5px rgba(0, 0, 0, 0.2), 4px 4px 8px rgba(0, 0, 0, 0.2);
}

/* Steel Theme */
#chat-container[data-chat-theme="steel"] .chat-message {
    background: linear-gradient(180deg, rgba(var(--theme-bg-rgb), var(--theme-bg-opacity)) 0%, rgba(var(--theme-bg-rgb), calc(var(--theme-bg-opacity) * 0.7)) 100%);
    border: 1px solid rgba(var(--theme-accent-rgb), var(--theme-accent-opacity));
    border-radius: 2px;
    padding: 10px 12px;
    margin-bottom: 8px;
    box-shadow: inset 0 1px 0 rgba(255, 255, 255, 0.2);
}

/* Luxury Theme */
#chat-container[data-chat-theme="luxury"] .chat-message {
    background-color: rgba(var(--theme-bg-rgb), var(--theme-bg-opacity));
    border: 1px solid rgba(var(--theme-accent-rgb), var(--theme-accent-opacity));
    border-top: 4px double rgba(var(--theme-accent-rgb), var(--theme-accent-opacity));
    border-bottom: 4px double rgba(var(--theme-accent-rgb), var(--theme-accent-opacity));
    padding: 10px 14px;
    margin-bottom: 12px;
}
#chat-container[data-chat-theme="luxury"] .username {
    border-bottom: 1px solid rgba(var(--theme-accent-rgb), var(--theme-accent-opacity));
    margin-right: 6px;
    font-weight: bold;
}

/* Blueprint Theme */
#chat-container[data-chat-theme="blueprint"] .chat-message {
    background-color: rgba(var(--theme-bg-rgb), var(--theme-bg-opacity));
    background-image:
        linear-gradient(rgba(var(--theme-accent-rgb), 0.15) 1px, transparent 1px),
        linear-gradient(90deg, rgba(var(--theme-accent-rgb), 0.15) 1px, transparent 1px);
    background-size: 20px 20px;
    border: 2px solid rgba(var(--theme-accent-rgb), var(--theme-accent-opacity));
    border-radius: 0;
    padding: 10px 14px;
    margin-bottom: 12px;
}

/* Winter Theme */
#chat-container[data-chat-theme="winter"] .chat-message {
    background: linear-gradient(180deg, rgba(var(--theme-bg-rgb), var(--theme-bg-opacity)) 0%, rgba(var(--theme-bg-rgb), calc(var(--theme-bg-opacity) * 0.8)) 100%);
    border: 1px solid rgba(var(--theme-accent-rgb), var(--theme-accent-opacity));
    border-radius: 12px 2px 12px 2px;
    padding: 10px 14px;
    margin-bottom: 10px;
    box-shadow: 0 0 8px rgba(173, 216, 230, 0.4);
}

/* Halloween Theme */
#chat-container[data-chat-theme="halloween"] .chat-message {
    background-color: rgba(var(--theme-bg-rgb), var(--theme-bg-opacity));
    border: 2px solid rgba(var(--theme-accent-rgb), var(--theme-accent-opacity));
    border-radius: 8px;
    padding: 10px 14px;
    margin-bottom: 12px;
    box-shadow: 0 0 8px rgba(var(--theme-accent-rgb), 0.4);
}
#chat-container[data-chat-theme="halloween"] .username {
    text-shadow: 1px 1px 0 #000;
    font-weight: bold;
    margin-right: 6px;
}

/* Ocean Theme */
#chat-container[data-chat-theme="ocean"] .chat-message {
    background: linear-gradient(180deg, rgba(var(--theme-bg-rgb), var(--theme-bg-opacity)) 0%, rgba(var(--theme-bg-rgb), calc(var(--theme-bg-opacity) * 0.8)) 100%);
    border: 1px solid rgba(var(--theme-accent-rgb), var(--theme-accent-opacity));
    border-radius: 20px 20px 20px 0;
    padding: 12px 16px;
    margin-bottom: 12px;
}

/* Rose Theme */
#chat-container[data-chat-theme="rose"] .chat-message {
    background-color: rgba(var(--theme-bg-rgb), var(--theme-bg-opacity));
    border: 1px solid rgba(var(--theme-accent-rgb), var(--theme-accent-opacity));
    border-left: 4px solid rgba(var(--theme-accent-rgb), var(--theme-accent-opacity));
    border-radius: 0 10px 10px 0;
    padding: 10px 14px;
    margin-bottom: 10px;
}
#chat-container[data-chat-theme="rose"] .username {
    font-style: italic;
    font-weight: bold;
    margin-right: 6px;
    border-bottom: 1px solid rgba(var(--theme-accent-rgb), var(--theme-accent-opacity));
}

/* Space Theme */
#chat-container[data-chat-theme="space"] .chat-message {
    background: linear-gradient(180deg, rgba(var(--theme-bg-rgb), var(--theme-bg-opacity)) 0%, rgba(var(--theme-bg-rgb), calc(var(--theme-bg-opacity) * 0.5)) 100%);
    border: 1px solid rgba(255, 255, 255, 0.15);
    border-radius: 8px;
    padding: 10px 14px;
    margin-bottom: 12px;
    box-shadow: 0 0 10px rgba(var(--theme-accent-rgb), 0.3);
}

/* Mint Theme */
#chat-container[data-chat-theme="mint"] .chat-message {
    background-color: rgba(var(--theme-bg-rgb), var(--theme-bg-opacity));
    border-left: 6px solid rgba(var(--theme-accent-rgb), var(--theme-accent-opacity));
    border-radius: 0 12px 12px 0;
    padding: 10px 14px;
    margin-bottom: 10px;
    box-shadow: 2px 2px 5px rgba(0, 0, 0, 0.05);
}
#chat-container[data-chat-theme="mint"] .username {
    color: rgba(var(--theme-accent-rgb), 1);
    font-weight: 800;
}

/* Glitch Theme */
#chat-container[data-chat-theme="glitch"] .chat-message {
    background-color: rgba(var(--theme-bg-rgb), var(--theme-bg-opacity));
    border: 1px solid rgba(var(--theme-accent-rgb), var(--theme-accent-opacity));
    padding: 10px 12px;
    margin-bottom: 12px;
    position: relative;
    box-shadow: -2px 0 0 rgba(255, 0, 0, 0.5), 2px 0 0 rgba(0, 255, 255, 0.5);
}
#chat-container[data-chat-theme="glitch"] .username {
    text-shadow: 2px 0 rgba(255, 0, 0, 0.5), -2px 0 rgba(0, 255, 255, 0.5);
    font-weight: bold;
    margin-right: 6px;
}

/* Sepia Theme */
#chat-container[data-chat-theme="sepia"] .chat-message {
    background-color: rgba(var(--theme-bg-rgb), var(--theme-bg-opacity));
    border: 1px solid rgba(var(--theme-accent-rgb), var(--theme-accent-opacity));
    border-radius: 2px;
    padding: 10px 14px;
    margin-bottom: 12px;
    box-shadow: 3px 3px 5px rgba(0, 0, 0, 0.1);
}
#chat-container[data-chat-theme="sepia"] .username {
    font-family: 'Noto Serif JP', serif;
    font-weight: bold;
    border-bottom: 1px solid rgba(var(--theme-accent-rgb), 0.3);
    margin-right: 6px;
}

/* Aurora Theme */
#chat-container[data-chat-theme="aurora"] .chat-message {
    background: linear-gradient(135deg, rgba(var(--theme-bg-rgb), var(--theme-bg-opacity)) 0%, rgba(var(--theme-accent-rgb), 0.2) 100%);
    border-top: 1px solid rgba(255, 255, 255, 0.3);
    border-left: 1px solid rgba(255, 255, 255, 0.3);
    border-radius: 12px;
    padding: 10px 14px;
    margin-bottom: 12px;
    box-shadow: 0 4px 15px rgba(var(--theme-accent-rgb), 0.2);
}

/* Fire Theme */
#chat-container[data-chat-theme="fire"] .chat-message {
    background: linear-gradient(to top, rgba(var(--theme-accent-rgb), 0.3) 0%, rgba(var(--theme-bg-rgb), var(--theme-bg-opacity)) 40%);
    border-bottom: 3px solid rgba(var(--theme-accent-rgb), 1);
    border-radius: 4px;
    padding: 10px 14px;
    margin-bottom: 12px;
}

/* Chalkboard Theme */
#chat-container[data-chat-theme="chalkboard"] .chat-message {
    background-color: rgba(var(--theme-bg-rgb), var(--theme-bg-opacity));
    border: 2px solid rgba(var(--theme-accent-rgb), 0.5);
    border-radius: 4px;
    padding: 10px 14px;
    margin-bottom: 12px;
    box-shadow: 2px 2px 0 rgba(255, 255, 255, 0.1);
}
#chat-container[data-chat-theme="chalkboard"] .username {
    text-decoration: underline;
    text-decoration-style: wavy;
    text-decoration-color: rgba(var(--theme-accent-rgb), 0.7);
    margin-right: 6px;
}

/* Rainbow Theme */
#chat-container[data-chat-theme="rainbow"] .chat-message {
    background-color: rgba(var(--theme-bg-rgb), var(--theme-bg-opacity));
    position: relative;
    padding: 10px 14px;
    margin-bottom: 12px;
    border-radius: 4px;
    box-shadow: 0 2px 5px rgba(0, 0, 0, 0.1);
    overflow: hidden;
}
#chat-container[data-chat-theme="rainbow"] .chat-message::before {
    content: "";
    position: absolute;
    top: 0;
    left: 0;
    width: 6px;
    height: 100%;
    background: linear-gradient(180deg, #ff0000, #ff7f00, #ffff00, #00ff00, #0000ff, #4b0082, #9400d3);
}

/* Ghost Theme */
#chat-container[data-chat-theme="ghost"] .chat-message {
    background-color: rgba(var(--theme-bg-rgb), var(--theme-bg-opacity));
    border: 1px solid rgba(255, 255, 255, 0.1);
    border-radius: 16px;
    padding: 10px 14px;
    margin-bottom: 12px;
    box-shadow: 0 0 15px rgba(255, 255, 255, 0.15);
    backdrop-filter: blur(2px);
}
#chat-container[data-chat-theme="ghost"] .username {
    text-shadow: 0 0 5px rgba(255, 255, 255, 0.5);
    margin-right: 6px;
}

/* Notebook Theme */
#chat-container[data-chat-theme="notebook"] .chat-message {
    background-color: rgba(var(--theme-bg-rgb), var(--theme-bg-opacity));
    border-left: 4px solid #ff6b6b;
    padding: 10px 14px;
    margin-bottom: 12px;
    box-shadow: 1px 1px 3px rgba(0, 0, 0, 0.1);
    background-image: repeating-linear-gradient(transparent, transparent 23px, rgba(0, 0, 0, 0.1) 24px);
}

/* Pop Art Theme */
#chat-container[data-chat-theme="popart"] .chat-message {
    background-color: rgba(var(--theme-bg-rgb), var(--theme-bg-opacity));
    background-image: radial-gradient(rgba(0, 0, 0, 0.2) 20%, transparent 20%);
    background-size: 8px 8px;
    border: 3px solid #000;
    box-shadow: 5px 5px 0 #000;
    padding: 12px;
    margin-bottom: 12px;
    border-radius: 0;
}
#chat-container[data-chat-theme="popart"] .username {
    background-color: #fff;
    border: 2px solid #000;
    padding: 2px 6px;
    margin-right: 6px;
    font-weight: 900;
    box-shadow: 2px 2px 0 #000;
}

/* Jewel Theme */
#chat-container[data-chat-theme="jewel"] .chat-message {
    background: linear-gradient(135deg, rgba(var(--theme-bg-rgb), var(--theme-bg-opacity)) 0%, rgba(var(--theme-bg-rgb), calc(var(--theme-bg-opacity) * 0.6)) 50%, rgba(var(--theme-bg-rgb), var(--theme-bg-opacity)) 100%);
    border: 1px solid rgba(255, 255, 255, 0.3);
    clip-path: polygon(10px 0, 100% 0, 100% calc(100% - 10px), calc(100% - 10px) 100%, 0 100%, 0 10px);
    padding: 12px 16px;
    margin-bottom: 10px;
}

/* 80s Theme */
#chat-container[data-chat-theme="80s"] .chat-message {
    background-color: rgba(var(--theme-bg-rgb), var(--theme-bg-opacity));
    border: 2px solid rgba(var(--theme-accent-rgb), var(--theme-accent-opacity));
    box-shadow: 4px 4px 0 #ff00ff, -2px -2px 0 #00ffff;
    padding: 10px 14px;
    margin-bottom: 12px;
    border-radius: 0;
}

/* Minecraft Theme */
#chat-container[data-chat-theme="minecraft"] .chat-message {
    background-color: rgba(var(--theme-bg-rgb), var(--theme-bg-opacity));
    border: 4px solid rgba(var(--theme-accent-rgb), var(--theme-accent-opacity));
    padding: 8px 12px;
    margin-bottom: 12px;
    image-rendering: pixelated;
    font-family: 'DotGothic16', sans-serif;
    box-shadow: inset 4px 4px 0 rgba(255, 255, 255, 0.2), inset -4px -4px 0 rgba(0, 0, 0, 0.2);
}

/* Newspaper Theme */
#chat-container[data-chat-theme="newspaper"] .chat-message {
    background-color: rgba(var(--theme-bg-rgb), var(--theme-bg-opacity));
    border-bottom: 1px solid rgba(0, 0, 0, 0.2);
    border-top: 1px solid rgba(0, 0, 0, 0.2);
    padding: 10px 0;
    margin-bottom: 8px;
    font-family: 'Noto Serif JP', serif;
    color: #2c2c2c;
}

/* Matrix Theme */
#chat-container[data-chat-theme="matrix"] .chat-message {
    background-color: rgba(0, 0, 0, 0.95);
    border: 1px solid #00ff00;
    padding: 10px;
    margin-bottom: 10px;
    font-family: 'Roboto Mono', monospace;
    box-shadow: 0 0 5px rgba(0, 255, 0, 0.5);
}
#chat-container[data-chat-theme="matrix"] .username {
    color: #00ff00;
    text-shadow: 0 0 4px #00ff00;
    margin-right: 8px;
}
#chat-container[data-chat-theme="matrix"] .message-body {
    color: #00ff00;
    text-shadow: 0 0 2px #00ff00;
}

/* Sakura Theme */
#chat-container[data-chat-theme="sakura"] .chat-message {
    background-color: rgba(var(--theme-bg-rgb), var(--theme-bg-opacity));
    border: 2px solid rgba(var(--theme-accent-rgb), 0.6);
    border-radius: 16px 0 16px 0;
    padding: 10px 14px;
    margin-bottom: 12px;
    box-shadow: 2px 2px 5px rgba(0, 0, 0, 0.05);
}
#chat-container[data-chat-theme="sakura"] .username {
    color: #d81b60;
    font-weight: bold;
    margin-right: 6px;
}

/* Sharp Theme */
#chat-container[data-chat-theme="sharp"] .chat-message {
    background: linear-gradient(90deg, rgba(var(--theme-bg-rgb), var(--theme-bg-opacity)) 0%, rgba(var(--theme-bg-rgb), calc(var(--theme-bg-opacity) * 0.8)) 100%);
    border-left: 6px solid rgba(var(--theme-accent-rgb), var(--theme-accent-opacity));
    transform: skewX(-10deg);
    padding: 10px 20px;
    margin-bottom: 12px;
    margin-left: 10px;
    border-radius: 2px;
}
#chat-container[data-chat-theme="sharp"] .username,
#chat-container[data-chat-theme="sharp"] .message-body {
    display: inline-block;
    transform: skewX(10deg);
}
#chat-container[data-chat-theme="sharp"] .username {
    font-weight: 800;
    text-transform: uppercase;
    margin-right: 8px;
}

/* Terminal Amber Theme */
#chat-container[data-chat-theme="terminal-amber"] .chat-message {
    background-color: rgba(0, 0, 0, 0.9);
    border-left: 2px solid #ffb000;
    padding: 6px 10px;
    margin-bottom: 6px;
    font-family: 'Roboto Mono', monospace;
    color: #ffb000;
    box-shadow: 0 0 4px rgba(255, 176, 0, 0.3);
}
#chat-container[data-chat-theme="terminal-amber"] .username {
    color: #ffb000;
}
#chat-container[data-chat-theme="terminal-amber"] .username::before {
    content: "> ";
}
#chat-container[data-chat-theme="terminal-amber"] .message-body {
    color: #ffb000;
}

/* Super Chat Theme */
#chat-container[data-chat-theme="superchat"] .chat-message {
    background-color: rgba(var(--theme-bg-rgb), var(--theme-bg-opacity));
    border-radius: 8px;
    padding: 0;
    margin-bottom: 12px;
    overflow: hidden;
    box-shadow: 0 2px 4px rgba(0,0,0,0.2);
}
#chat-container[data-chat-theme="superchat"] .username {
    display: block;
    background-color: rgba(var(--theme-accent-rgb), var(--theme-accent-opacity));
    color: #fff; /* ヘッダー文字色は白固定 */
    padding: 6px 12px;
    font-weight: bold;
    font-size: 0.9em;
}
#chat-container[data-chat-theme="superchat"] .message-body {
    display: block;
    padding: 10px 12px;
}

/* Cinematic Theme */
#chat-container[data-chat-theme="cinematic"] .chat-message {
    background: linear-gradient(to right, transparent 0%, rgba(0, 0, 0, 0.8) 20%, rgba(0, 0, 0, 0.8) 80%, transparent 100%);
    border-top: 1px solid rgba(var(--theme-accent-rgb), 0.3);
    border-bottom: 1px solid rgba(var(--theme-accent-rgb), 0.3);
    padding: 12px 20px;
    margin-bottom: 16px;
    text-align: center;
    font-family: 'Noto Serif JP', serif;
}
#chat-container[data-chat-theme="cinematic"] .username {
    display: block;
    font-size: 0.8em;
    opacity: 0.7;
    margin-bottom: 4px;
    margin-right: 0;
}

/* RPG Theme */
#chat-container[data-chat-theme="rpg"] .chat-message {
    background-color: rgba(0, 0, 128, 0.9); /* Navy */
    border: 2px solid #ffffff;
    border-radius: 8px;
    padding: 10px 14px;
    margin-bottom: 12px;
    box-shadow: 0 0 0 2px rgba(0, 0, 0, 0.5), inset 0 0 0 2px rgba(0, 0, 0, 0.5);
    font-family: 'DotGothic16', sans-serif;
}
#chat-container[data-chat-theme="rpg"] .username {
    color: #ffffff;
    text-shadow: 2px 2px 0 #000000;
}
#chat-container[data-chat-theme="rpg"] .message-body {
    color: #ffffff;
    text-shadow: 2px 2px 0 #000000;
}

/* Sci-Fi Theme */
#chat-container[data-chat-theme="sci-fi"] .chat-message {
    background-color: rgba(var(--theme-bg-rgb), 0.8);
    border: 1px solid rgba(var(--theme-accent-rgb), 0.5);
    border-left: 4px solid rgba(var(--theme-accent-rgb), 1);
    border-right: 4px solid rgba(var(--theme-accent-rgb), 1);
    padding: 10px 16px;
    margin-bottom: 12px;
    clip-path: polygon(10px 0, 100% 0, 100% calc(100% - 10px), calc(100% - 10px) 100%, 0 100%, 0 10px);
}
#chat-container[data-chat-theme="sci-fi"] .username {
    letter-spacing: 1px;
    text-transform: uppercase;
    color: rgba(var(--theme-accent-rgb), 1);
}

/* Dream Theme */
#chat-container[data-chat-theme="dream"] .chat-message {
    background: linear-gradient(120deg, rgba(255, 228, 225, 0.9) 0%, rgba(230, 230, 250, 0.9) 100%);
    border-radius: 20px;
    padding: 12px 16px;
    margin-bottom: 12px;
    box-shadow: 0 4px 10px rgba(255, 182, 193, 0.4);
    border: 1px solid rgba(255, 255, 255, 0.8);
}
#chat-container[data-chat-theme="dream"] .username {
    color: #9370db;
    font-weight: bold;
}

/* Gameboy Theme */
#chat-container[data-chat-theme="gameboy"] .chat-message {
    background-color: #8bac0f;
    border: 3px solid #0f380f;
    padding: 10px;
    margin-bottom: 12px;
    font-family: 'DotGothic16', sans-serif;
    color: #0f380f;
    border-radius: 4px;
    box-shadow: inset 2px 2px 0 rgba(0,0,0,0.1);
}
#chat-container[data-chat-theme="gameboy"] .username {
    color: #0f380f;
    font-weight: bold;
    text-transform: uppercase;
}
#chat-container[data-chat-theme="gameboy"] .message-body {
    color: #0f380f;
}

/* Clouds Theme */
#chat-container[data-chat-theme="clouds"] .chat-message {
    background: linear-gradient(180deg, rgba(var(--theme-bg-rgb), 0.9) 0%, rgba(255, 255, 255, 0.8) 100%);
    border: 2px solid #ffffff;
    border-radius: 20px;
    padding: 12px 16px;
    margin-bottom: 12px;
    box-shadow: 0 4px 8px rgba(135, 206, 235, 0.3);
}
#chat-container[data-chat-theme="clouds"] .username {
    color: #00bfff;
    font-weight: bold;
    text-shadow: 1px 1px 0 #ffffff;
}

/* Party Theme */
#chat-container[data-chat-theme="party"] .chat-message {
    background-color: rgba(var(--theme-bg-rgb), var(--theme-bg-opacity));
    background-image: radial-gradient(rgba(var(--theme-accent-rgb), 0.2) 15%, transparent 16%), radial-gradient(rgba(var(--theme-accent-rgb), 0.2) 15%, transparent 16%);
    background-size: 20px 20px;
    background-position: 0 0, 10px 10px;
    border: 2px dashed rgba(var(--theme-accent-rgb), 1);
    border-radius: 10px;
    padding: 12px;
    margin-bottom: 12px;
    transform: rotate(-1deg);
}
#chat-container[data-chat-theme="party"] .chat-message:nth-child(even) {
    transform: rotate(1deg);
}
#chat-container[data-chat-theme="party"] .username {
    font-weight: 900;
    background: #fff;
    padding: 2px 6px;
    border-radius: 4px;
    margin-right: 6px;
}

/* Steampunk Theme */
#chat-container[data-chat-theme="steampunk"] .chat-message {
    background-color: rgba(var(--theme-bg-rgb), var(--theme-bg-opacity));
    border: 4px ridge rgba(var(--theme-accent-rgb), 1);
    border-radius: 4px;
    padding: 10px 14px;
    margin-bottom: 12px;
    box-shadow: inset 0 0 20px rgba(0, 0, 0, 0.5);
}
#chat-container[data-chat-theme="steampunk"] .username {
    font-family: 'Noto Serif JP', serif;
    color: rgba(var(--theme-accent-rgb), 1);
    border-bottom: 1px dashed rgba(var(--theme-accent-rgb), 0.5);
    margin-right: 6px;
    font-weight: bold;
}

/* Art Deco Theme */
#chat-container[data-chat-theme="artdeco"] .chat-message {
    background-color: rgba(var(--theme-bg-rgb), var(--theme-bg-opacity));
    border: 2px solid rgba(var(--theme-accent-rgb), 1);
    outline: 1px solid rgba(var(--theme-accent-rgb), 0.6);
    outline-offset: 4px;
    margin: 6px 6px 16px 6px;
    padding: 12px;
}
#chat-container[data-chat-theme="artdeco"] .username {
    text-transform: uppercase;
    letter-spacing: 2px;
    border-bottom: 2px solid rgba(var(--theme-accent-rgb), 1);
    margin-bottom: 4px;
    margin-right: 8px;
    display: inline-block;
    font-weight: bold;
}

/* Mosaic Theme */
#chat-container[data-chat-theme="mosaic"] .chat-message {
    background-color: rgba(var(--theme-bg-rgb), var(--theme-bg-opacity));
    background-image: linear-gradient(45deg, rgba(0, 0, 0, 0.03) 25%, transparent 25%, transparent 75%, rgba(0, 0, 0, 0.03) 75%, rgba(0, 0, 0, 0.03)),
                      linear-gradient(45deg, rgba(0, 0, 0, 0.03) 25%, transparent 25%, transparent 75%, rgba(0, 0, 0, 0.03) 75%, rgba(0, 0, 0, 0.03));
    background-size: 20px 20px;
    background-position: 0 0, 10px 10px;
    border: 1px solid rgba(var(--theme-accent-rgb), 0.2);
    padding: 10px 14px;
    margin-bottom: 12px;
    border-radius: 8px;
}

/* Card Dark Theme */
#chat-container[data-chat-theme="card-dark"] .chat-message {
    background-color: #212121;
    border-left: 4px solid rgba(var(--theme-accent-rgb), 1);
    border-radius: 4px;
    padding: 12px;
    margin-bottom: 10px;
    box-shadow: 0 2px 5px rgba(0,0,0,0.5);
}

/* Street Theme */
#chat-container[data-chat-theme="street"] .chat-message {
    background-color: #111;
    border: 3px solid rgba(var(--theme-accent-rgb), 1);
    padding: 10px;
    margin-bottom: 12px;
    transform: skew(-5deg);
    box-shadow: 5px 5px 0 rgba(var(--theme-accent-rgb), 0.5);
}
#chat-container[data-chat-theme="street"] .username {
    background: rgba(var(--theme-accent-rgb), 1);
    color: #000;
    padding: 2px 5px;
    font-weight: 900;
    text-transform: uppercase;
}

/* Warm Theme */
#chat-container[data-chat-theme="warm"] .chat-message {
    background: linear-gradient(to bottom right, rgba(var(--theme-bg-rgb), var(--theme-bg-opacity)), rgba(255, 224, 178, var(--theme-bg-opacity)));
    border-radius: 15px;
    padding: 12px 16px;
    margin-bottom: 12px;
    border: 1px solid rgba(var(--theme-accent-rgb), 0.3);
    box-shadow: 0 2px 4px rgba(161, 136, 127, 0.2);
}

/* CRT Theme */
#chat-container[data-chat-theme="crt"] .chat-message {
    background-color: rgba(0, 20, 0, 0.9);
    border: 1px solid #33ff33;
    padding: 10px;
    margin-bottom: 12px;
    font-family: 'Roboto Mono', monospace;
    color: #33ff33;
    box-shadow: 0 0 10px rgba(51, 255, 51, 0.5), inset 0 0 20px rgba(0, 0, 0, 0.8);
    background-image: linear-gradient(rgba(18, 16, 16, 0) 50%, rgba(0, 0, 0, 0.25) 50%), linear-gradient(90deg, rgba(255, 0, 0, 0.06), rgba(0, 255, 0, 0.02), rgba(0, 0, 255, 0.06));
    background-size: 100% 2px, 3px 100%;
}
#chat-container[data-chat-theme="crt"] .username {
    color: #33ff33;
    text-shadow: 2px 0 0 rgba(255,0,0,0.5), -2px 0 0 rgba(0,0,255,0.5);
}
#chat-container[data-chat-theme="crt"] .message-body {
    color: #33ff33;
    text-shadow: 0 0 5px #33ff33;
}

/* Playful Theme */
#chat-container[data-chat-theme="playful"] .chat-message {
    background-color: rgba(var(--theme-bg-rgb), var(--theme-bg-opacity));
    border: 3px solid rgba(var(--theme-accent-rgb), 1);
    border-radius: 20px 5px 20px 5px;
    padding: 12px 16px;
    margin-bottom: 12px;
    box-shadow: 4px 4px 0 rgba(0,0,0,0.1);
}
#chat-container[data-chat-theme="playful"] .chat-message:nth-child(even) {
    border-radius: 5px 20px 5px 20px;
}

/* Journal Theme */
#chat-container[data-chat-theme="journal"] .chat-message {
    background-color: rgba(var(--theme-bg-rgb), var(--theme-bg-opacity));
    color: #4a4a4a;
    padding: 15px 15px 10px 15px;
    margin-bottom: 16px;
    box-shadow: 2px 2px 5px rgba(0,0,0,0.2);
    position: relative;
    transform: rotate(-1deg);
}
#chat-container[data-chat-theme="journal"] .chat-message:nth-child(even) {
    transform: rotate(1deg);
}
#chat-container[data-chat-theme="journal"] .chat-message::before {
    content: "";
    position: absolute;
    top: -8px;
    left: 50%;
    transform: translateX(-50%);
    width: 60px;
    height: 20px;
    background-color: rgba(var(--theme-accent-rgb), 0.5);
    opacity: 0.7;
    box-shadow: 0 1px 2px rgba(0,0,0,0.1);
}

/* Ticket Theme */
#chat-container[data-chat-theme="ticket"] .chat-message {
    background-color: transparent;
    background-image: 
        radial-gradient(circle at 0 50%, transparent 10px, rgba(var(--theme-bg-rgb), var(--theme-bg-opacity)) 10.5px),
        radial-gradient(circle at 100% 50%, transparent 10px, rgba(var(--theme-bg-rgb), var(--theme-bg-opacity)) 10.5px);
    background-size: 51% 100%;
    background-position: left, right;
    background-repeat: no-repeat;
    padding: 12px 24px;
    margin-bottom: 12px;
    filter: drop-shadow(0 2px 3px rgba(0,0,0,0.2));
}
#chat-container[data-chat-theme="ticket"] .username {
    border-bottom: 1px dashed rgba(var(--theme-accent-rgb), 0.5);
    margin-right: 6px;
    font-weight: bold;
}

/* Neo-Brutalism Theme */
#chat-container[data-chat-theme="neobrutalism"] .chat-message {
    background-color: rgba(var(--theme-bg-rgb), var(--theme-bg-opacity));
    border: 3px solid #000;
    box-shadow: 4px 4px 0 #000;
    border-radius: 0;
    padding: 12px;
    margin-bottom: 12px;
}

/* Keyboard Theme */
#chat-container[data-chat-theme="keyboard"] .chat-message {
    background-color: rgba(var(--theme-bg-rgb), var(--theme-bg-opacity));
    border: 1px solid rgba(0,0,0,0.2);
    border-bottom: 4px solid rgba(0,0,0,0.3);
    border-radius: 8px;
    padding: 10px 14px;
    margin-bottom: 12px;
}

/* Pixel Theme */
#chat-container[data-chat-theme="pixel"] .chat-message {
    background-color: rgba(var(--theme-bg-rgb), var(--theme-bg-opacity));
    border: 4px solid rgba(var(--theme-accent-rgb), 1);
    image-rendering: pixelated;
    font-family: 'DotGothic16', sans-serif;
    box-shadow: 4px 4px 0 rgba(0,0,0,0.5);
    margin-bottom: 12px;
    padding: 10px;
}

/* Gradient Theme */
#chat-container[data-chat-theme="gradient"] .chat-message {
    background: linear-gradient(135deg, rgba(var(--theme-bg-rgb), var(--theme-bg-opacity)), rgba(var(--theme-accent-rgb), 0.5));
    border-radius: 16px;
    padding: 12px 16px;
    margin-bottom: 12px;
    box-shadow: 0 4px 15px rgba(var(--theme-accent-rgb), 0.3);
}

/* Sketch Theme */
#chat-container[data-chat-theme="sketch"] .chat-message {
    background-color: rgba(var(--theme-bg-rgb), var(--theme-bg-opacity));
    border: 2px solid rgba(var(--theme-accent-rgb), 0.8);
    border-radius: 2px 255px 3px 25px / 255px 5px 225px 3px;
    padding: 12px 16px;
    margin-bottom: 12px;
    font-family: 'Yusei Magic', sans-serif;
    box-shadow: 2px 2px 5px rgba(0,0,0,0.1);
}

/* Win95 Theme */
#chat-container[data-chat-theme="win95"] .chat-message {
    background-color: #c0c0c0;
    border-top: 2px solid #ffffff;
    border-left: 2px solid #ffffff;
    border-right: 2px solid #808080;
    border-bottom: 2px solid #808080;
    padding: 8px 12px;
    margin-bottom: 12px;
    color: #000000;
    box-shadow: 1px 1px 0 #000000;
    border-radius: 0;
}
#chat-container[data-chat-theme="win95"] .username {
    color: #000080;
    font-weight: bold;
}
#chat-container[data-chat-theme="win95"] .message-body {
    color: #000000;
}

/* Sticker Theme */
#chat-container[data-chat-theme="sticker"] .chat-message {
    background-color: rgba(var(--theme-bg-rgb), var(--theme-bg-opacity));
    border: 3px solid #ffffff;
    border-radius: 12px;
    padding: 10px 14px;
    margin-bottom: 12px;
    box-shadow: 0 4px 6px rgba(0,0,0,0.15);
}

/* Notebook Dark Theme */
#chat-container[data-chat-theme="notebook-dark"] .chat-message {
    background-color: rgba(var(--theme-bg-rgb), var(--theme-bg-opacity));
    border-left: 4px solid rgba(var(--theme-accent-rgb), 0.5);
    padding: 10px 14px;
    margin-bottom: 12px;
    background-image: repeating-linear-gradient(transparent, transparent 23px, rgba(255, 255, 255, 0.05) 24px);
}

/* Clean Theme */
#chat-container[data-chat-theme="clean"] .chat-message {
    background-color: rgba(var(--theme-bg-rgb), var(--theme-bg-opacity));
    border: 1px solid rgba(0,0,0,0.05);
    border-radius: 8px;
    padding: 12px 16px;
    margin-bottom: 12px;
    box-shadow: 0 2px 8px rgba(0,0,0,0.05);
}
#chat-container[data-chat-theme="clean"] .username {
    font-weight: 600;
    color: rgba(var(--theme-accent-rgb), 1);
}

/* Impact Theme */
#chat-container[data-chat-theme="impact"] .chat-message {
    background-color: rgba(var(--theme-bg-rgb), var(--theme-bg-opacity));
    border: 4px solid #000;
    padding: 12px;
    margin-bottom: 12px;
    font-weight: 900;
}
#chat-container[data-chat-theme="impact"] .username {
    background: #000;
    color: #fff;
    padding: 2px 6px;
    display: inline-block;
    margin-right: 8px;
    text-transform: uppercase;
}

/* Vintage Theme */
#chat-container[data-chat-theme="vintage"] .chat-message {
    background-color: rgba(var(--theme-bg-rgb), var(--theme-bg-opacity));
    border: 1px solid rgba(var(--theme-accent-rgb), 0.4);
    outline: 1px solid rgba(var(--theme-accent-rgb), 0.4);
    outline-offset: -5px;
    padding: 14px;
    margin-bottom: 14px;
    font-family: 'Noto Serif JP', serif;
}
#chat-container[data-chat-theme="vintage"] .username {
    border-bottom: 1px solid rgba(var(--theme-accent-rgb), 0.5);
    margin-right: 6px;
    font-style: italic;
}

/* Material Theme */
#chat-container[data-chat-theme="material"] .chat-message {
    background-color: rgba(var(--theme-bg-rgb), var(--theme-bg-opacity));
    border-radius: 4px;
    padding: 12px 16px;
    margin-bottom: 12px;
    box-shadow: 0 1px 3px rgba(0,0,0,0.12), 0 1px 2px rgba(0,0,0,0.24);
    border: none;
}

/* Terminal Green Theme */
#chat-container[data-chat-theme="terminal-green"] .chat-message {
    background-color: rgba(0, 0, 0, 0.9);
    border-left: 2px solid #00ff00;
    padding: 6px 10px;
    margin-bottom: 6px;
    font-family: 'Roboto Mono', monospace;
    color: #00ff00;
    box-shadow: 0 0 4px rgba(0, 255, 0, 0.3);
}
#chat-container[data-chat-theme="terminal-green"] .username {
    color: #00ff00;
}
#chat-container[data-chat-theme="terminal-green"] .username::before {
    content: "> ";
}
#chat-container[data-chat-theme="terminal-green"] .message-body {
    color: #00ff00;
}

/* Soft Theme */
#chat-container[data-chat-theme="soft"] .chat-message {
    background-color: rgba(var(--theme-bg-rgb), var(--theme-bg-opacity));
    border-radius: 20px;
    padding: 12px 18px;
    margin-bottom: 12px;
    box-shadow: 0 2px 10px rgba(0,0,0,0.05);
}

/* Aqua Theme */
#chat-container[data-chat-theme="aqua"] .chat-message {
    background: linear-gradient(to bottom, rgba(255,255,255,0.9) 0%, rgba(230,240,255,0.9) 50%, rgba(200,225,255,0.9) 51%, rgba(240,250,255,0.9) 100%);
    border: 1px solid #a0c0e0;
    border-radius: 15px;
    padding: 10px 16px;
    margin-bottom: 12px;
    box-shadow: 0 2px 4px rgba(0,0,0,0.1);
}
#chat-container[data-chat-theme="aqua"] .username {
    color: #007aff;
    font-weight: bold;
    text-shadow: 0 1px 0 #ffffff;
}

/* Lava Theme */
#chat-container[data-chat-theme="lava"] .chat-message {
    background: linear-gradient(45deg, rgba(51,0,0,0.9), rgba(102,0,0,0.9));
    border-bottom: 4px solid #ff4500;
    border-radius: 8px 8px 0 0;
    padding: 12px;
    margin-bottom: 12px;
    box-shadow: 0 0 10px rgba(255, 69, 0, 0.3);
}
#chat-container[data-chat-theme="lava"] .username {
    color: #ffcc00;
    text-shadow: 2px 2px 0 #000000;
}

/* Desert Theme */
#chat-container[data-chat-theme="desert"] .chat-message {
    background-color: rgba(244, 228, 188, 0.95);
    border: 2px solid #8b4513;
    border-radius: 4px;
    padding: 10px 14px;
    margin-bottom: 12px;
}
#chat-container[data-chat-theme="desert"] .username {
    color: #8b4513;
    font-weight: bold;
    border-bottom: 1px dotted #8b4513;
    margin-right: 6px;
}

/* Simple Dark Theme */
#chat-container[data-chat-theme="simple-dark"] .chat-message {
    background-color: rgba(var(--theme-bg-rgb), var(--theme-bg-opacity));
    border-left: 3px solid rgba(var(--theme-accent-rgb), 0.8);
    padding: 8px 12px;
    margin-bottom: 8px;
    border-radius: 2px;
    box-shadow: 0 1px 2px rgba(0,0,0,0.3);
}

/* Elegant Theme */
#chat-container[data-chat-theme="elegant"] .chat-message {
    background: linear-gradient(to right, rgba(var(--theme-bg-rgb), var(--theme-bg-opacity)), transparent);
    border-bottom: 1px solid rgba(var(--theme-accent-rgb), 0.4);
    padding: 10px 14px;
    margin-bottom: 12px;
    font-family: 'Noto Serif JP', serif;
}
#chat-container[data-chat-theme="elegant"] .username {
    color: rgba(var(--theme-accent-rgb), 1);
    font-style: italic;
    margin-right: 8px;
    font-weight: normal;
}

/* Techno Theme */
#chat-container[data-chat-theme="techno"] .chat-message {
    background-color: rgba(var(--theme-bg-rgb), var(--theme-bg-opacity));
    border-left: 2px solid rgba(var(--theme-accent-rgb), 1);
    border-right: 2px solid rgba(var(--theme-accent-rgb), 1);
    padding: 10px 14px;
    margin-bottom: 12px;
    position: relative;
}
#chat-container[data-chat-theme="techno"] .chat-message::before,
#chat-container[data-chat-theme="techno"] .chat-message::after {
    content: "";
    position: absolute;
    width: 8px;
    height: 8px;
    border-top: 4px solid rgba(var(--theme-accent-rgb), 1);
    top: 0;
}
#chat-container[data-chat-theme="techno"] .chat-message::before { left: 0; border-left: 2px solid rgba(var(--theme-accent-rgb), 1); }
#chat-container[data-chat-theme="techno"] .chat-message::after { right: 0; border-right: 2px solid rgba(var(--theme-accent-rgb), 1); }

/* Noir Theme */
#chat-container[data-chat-theme="noir"] .chat-message {
    background-color: #000000;
    border: 1px solid #333333;
    border-left: 4px solid #ffffff;
    padding: 12px;
    margin-bottom: 12px;
    color: #e0e0e0;
    box-shadow: 4px 4px 0 rgba(255, 255, 255, 0.1);
}
#chat-container[data-chat-theme="noir"] .username {
    color: #ffffff;
    font-weight: bold;
    text-transform: uppercase;
    letter-spacing: 1px;
}

/* Flux Theme */
#chat-container[data-chat-theme="flux"] .chat-message {
    background: linear-gradient(135deg, rgba(var(--theme-bg-rgb), 0.8), rgba(var(--theme-accent-rgb), 0.1));
    border-radius: 16px 4px 16px 4px;
    padding: 12px 16px;
    margin-bottom: 12px;
    backdrop-filter: blur(5px);
}

/* Grid Theme */
#chat-container[data-chat-theme="grid"] .chat-message {
    background-color: rgba(var(--theme-bg-rgb), var(--theme-bg-opacity));
    background-image:
        linear-gradient(rgba(var(--theme-accent-rgb), 0.2) 1px, transparent 1px),
        linear-gradient(90deg, rgba(var(--theme-accent-rgb), 0.2) 1px, transparent 1px);
    background-size: 20px 20px;
    border: 1px solid rgba(var(--theme-accent-rgb), 0.5);
    padding: 10px 14px;
    margin-bottom: 12px;
}

/* Minimal Theme */
#chat-container[data-chat-theme="minimal"] .chat-message {
    margin-bottom: 1px;
    font-size: 0.95em;
    padding: 0;
}

/* Text Outline Override (Apply to all themes if enabled) */
#chat-container .chat-message .username,
#chat-container .chat-message .message-body {
    text-shadow: var(--text-outline-style);
}

/* --- Modal --- */
.modal {
    position: fixed;
    z-index: 2000;
    left: 0;
    top: 0;
    width: 100%;
    height: 100%;
    background-color: rgba(0, 0, 0, 0.5);
    display: flex;
    justify-content: center;
    align-items: center;
    opacity: 1;
    transition: opacity 0.2s ease;
    visibility: visible;
}

.modal.hidden {
    opacity: 0;
    visibility: hidden;
    pointer-events: none;
}

.modal-content {
    background-color: var(--bg-secondary);
    color: var(--text-primary);
    padding: 24px;
    border-radius: 8px;
    width: 90%;
    max-width: 600px;
    max-height: 85vh;
    overflow-y: auto;
    position: relative;
    box-shadow: 0 10px 25px rgba(0, 0, 0, 0.5);
    border: 1px solid var(--bg-tertiary);
}

.close-btn {
    position: absolute;
    top: 12px;
    right: 16px;
    color: var(--text-secondary);
    font-size: 28px;
    font-weight: bold;
    cursor: pointer;
    line-height: 1;
}

.close-btn:hover {
    color: var(--text-primary);
}

.modal-body h2 {
    margin-top: 0;
    margin-bottom: 16px;
    font-size: 1.5rem;
    border-bottom: 1px solid var(--bg-tertiary);
    padding-bottom: 10px;
    color: var(--accent-primary);
}

.modal-body h3 {
    margin-top: 16px;
    margin-bottom: 8px;
    font-size: 1.1rem;
    color: var(--text-primary);
}

.modal-body p {
    margin-bottom: 12px;
    line-height: 1.6;
    color: var(--text-secondary);
}

.modal-body ul {
    margin-bottom: 12px;
    padding-left: 24px;
    list-style-type: disc;
    color: var(--text-secondary);
}

.modal-body li {
    margin-bottom: 4px;
}

/* --- Contact List Styles --- */
.modal-body .contact-list {
    list-style: none;
    padding-left: 0;
    margin-top: 16px;
}

.contact-link {
    display: flex;
    align-items: center;
    padding: 16px;
    background-color: var(--bg-tertiary);
    border-radius: 8px;
    text-decoration: none;
    color: var(--text-primary);
    transition: background-color 0.2s, color 0.2s;
    border: 1px solid transparent;
}

.contact-link:hover {
    background-color: var(--accent-primary);
    color: #ffffff;
    border-color: rgba(255, 255, 255, 0.2);
}

.contact-link i {
    font-size: 1.5rem;
    margin-right: 16px;
    width: 30px;
    text-align: center;
}

.contact-link span {
    font-weight: bold;
    font-size: 1.05rem;
}

/* --- Share Buttons --- */
.share-area {
    padding-top: 10px;
    border-top: 1px solid var(--bg-tertiary);
}

.share-btn-x {
    background-color: #000000;
    color: #ffffff;
    display: flex;
    justify-content: center;
    align-items: center;
    gap: 10px;
    font-weight: bold;
    text-decoration: none;
    margin-bottom: 10px;
}

.share-btn-x:hover {
    background-color: #9147ff;
}

/* --- Sidebar Footer --- */
.sidebar-footer {
    margin-top: 24px;
    text-align: center;
    color: var(--text-secondary);
    font-size: 0.8rem;
    padding-bottom: 16px;
}