* { box-sizing: border-box; }
:root {
    --bg: #f6f8fb;
    --surface: #ffffff;
    --text: #0f172a;
    --muted: #5b6476;
    --border: #e2e8f0;
    --primary: #2563eb;
    --primary-strong: #1d4ed8;
    --chip-bg: #e0f2fe;
    --chip-text: #0369a1;
    --shadow: 0 20px 60px rgba(15,23,42,0.08);
    --bubble-self: #e8f1ff;
    --bubble-other: #ffffff;
    --panel-grad: radial-gradient(120% 120% at 12% 22%, #dbeafe 0, #eff6ff 35%, #f8fafc 60%);
}
:root[data-theme="dark"], body[data-theme="dark"] {
    --bg: #0b1220;
    --surface: #0f172a;
    --text: #e2e8f0;
    --muted: #94a3b8;
    --border: #1f2937;
    --primary: #60a5fa;
    --primary-strong: #3b82f6;
    --chip-bg: #3b82f6;
    --chip-text: #ffffff;
    --shadow: 0 16px 50px rgba(0,0,0,0.45);
    --bubble-self: #132a4a;
    --bubble-other: #0f172a;
    --panel-grad: radial-gradient(120% 120% at 12% 22%, #0f172a 0, #0b1220 42%, #0b1220 70%);
}

html, body {
    height: 100%;
    margin: 0;
    padding: 0;
    overflow: hidden;
}
body {
    font-family: "Inter", system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
    background: var(--bg);
    color: var(--text);
    transition: background 0.2s ease, color 0.2s ease;
}
a { color: var(--primary); text-decoration: none; }
.landing-bg {
    min-height: 100vh;
    background: var(--panel-grad);
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    padding: 32px 18px 40px;
}
.landing-container {
    width: 100%;
    max-width: 600px;
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 32px;
}
.landing-footer {
    width: 100%;
    max-width: 600px;
    margin: 80px auto 20px;
    text-align: center;
}
.landing-footer p {
    color: #94a3b8;
    font-size: 12px;
    margin: 0;
    opacity: 0.6;
}
:root[data-theme="dark"] .landing-footer p,
body[data-theme="dark"] .landing-footer p {
    color: #64748b;
    opacity: 0.5;
}
.landing-hero {
    text-align: center;
}
.landing-hero h1 {
    font-size: 48px;
    font-weight: 800;
    margin: 0 0 12px;
    background: linear-gradient(135deg, var(--primary), #8b5cf6);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}
.landing-subtitle {
    font-size: 18px;
    color: var(--muted);
    margin: 0 0 32px;
}
.large-btn {
    padding: 16px 32px;
    font-size: 18px;
    border-radius: 16px;
}
.create-form-container {
    width: 100%;
    animation: fadeIn 0.3s ease;
}
@keyframes fadeIn {
    from { opacity: 0; transform: translateY(10px); }
    to { opacity: 1; transform: translateY(0); }
}
.chat-bg {
    height: 100vh;
    height: 100dvh; /* Use dynamic viewport height for mobile */
    overflow: hidden;
    background: 
        radial-gradient(circle at 20% 50%, rgba(99, 102, 241, 0.08) 0%, transparent 50%),
        radial-gradient(circle at 80% 80%, rgba(236, 72, 153, 0.08) 0%, transparent 50%),
        radial-gradient(circle at 40% 20%, rgba(59, 130, 246, 0.06) 0%, transparent 50%),
        linear-gradient(180deg, var(--bg) 0%, rgba(99,102,241,0.03) 100%);
    background-attachment: fixed;
}
:root[data-theme="dark"] .chat-bg,
body[data-theme="dark"] .chat-bg {
    background: 
        radial-gradient(circle at 20% 50%, rgba(99, 102, 241, 0.12) 0%, transparent 50%),
        radial-gradient(circle at 80% 80%, rgba(236, 72, 153, 0.12) 0%, transparent 50%),
        radial-gradient(circle at 40% 20%, rgba(59, 130, 246, 0.1) 0%, transparent 50%),
        linear-gradient(180deg, var(--bg) 0%, rgba(15, 23, 42, 0.95) 100%);
    background-attachment: fixed;
}
.glass {
    background: rgba(255,255,255,0.9);
    border: 1px solid var(--border);
    border-radius: 18px;
    box-shadow: var(--shadow);
    padding: 20px;
}
:root[data-theme="dark"] .glass,
body[data-theme="dark"] .glass {
    background: rgba(15,23,42,0.72);
}
.badge {
    display: inline-block;
    padding: 6px 12px;
    background: var(--chip-bg);
    color: var(--chip-text);
    border-radius: 12px;
    font-weight: 700;
    font-size: 13px;
    letter-spacing: 0.4px;
}
.label {
    display: block;
    margin: 12px 0 6px;
    font-weight: 600;
}
.required { color: var(--primary); }
input, textarea, button { font-family: inherit; }
input, textarea {
    width: 100%;
    padding: 12px 14px;
    border-radius: 12px;
    border: 1px solid var(--border);
    background: var(--surface);
    color: var(--text);
    font-size: 16px; /* 16px prevents auto-zoom on mobile */
    transition: border 0.2s, box-shadow 0.2s;
}
input:focus, textarea:focus {
    outline: none;
    border-color: var(--primary);
    box-shadow: 0 0 0 3px rgba(37,99,235,0.15);
}
button {
    border: none;
    border-radius: 12px;
    padding: 12px 14px;
    font-weight: 700;
    cursor: pointer;
    transition: transform 0.1s ease, box-shadow 0.2s ease;
}
button:active { transform: translateY(1px); }
.primary {
    background: linear-gradient(135deg, var(--primary), var(--primary-strong));
    color: #fff;
    box-shadow: 0 8px 20px rgba(37,99,235,0.25);
}
.secondary {
    background: #e0e7ff;
    color: #4338ca;
}
:root[data-theme="dark"] .secondary,
body[data-theme="dark"] .secondary {
    background: #1e293b;
    color: #cbd5f5;
}
.ghost-btn {
    background: transparent;
    color: var(--text);
    border: 1px solid var(--border);
}
.mini-btn {
    padding: 8px 10px;
    font-size: 13px;
    border-radius: 10px;
}
.full-width { width: 100%; }
.muted { color: var(--muted); }
.small { font-size: 13px; }
.mini { font-size: 12px; }
.inline-input {
    display: flex;
    gap: 8px;
    align-items: center;
}
.pill-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(140px, 1fr));
    gap: 8px;
}
.pill-grid.compact { grid-template-columns: repeat(auto-fill, minmax(120px, 1fr)); }
.pill {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 10px 12px;
    background: rgba(248,250,252,0.7);
    border: 1px solid var(--border);
    border-radius: 12px;
    cursor: pointer;
    font-weight: 600;
}
.pill input { width: auto; margin: 0; }
.avatar-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(70px, 1fr));
    gap: 10px;
    margin: 8px 0 4px;
}
.avatar-grid.small { grid-template-columns: repeat(auto-fill, minmax(52px, 1fr)); }
.avatar-pill {
    display: flex;
    justify-content: center;
    align-items: center;
    gap: 6px;
    padding: 8px;
    border: 1px solid var(--border);
    border-radius: 12px;
    background: var(--surface);
    cursor: pointer;
}
.avatar-pill input { width: auto; margin: 0; }
.avatar-pill img {
    width: 42px;
    height: 42px;
    border-radius: 12px;
    background: #f1f5f9;
}
.emoji-avatar {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 42px;
    height: 42px;
    border-radius: 12px;
    font-size: 24px;
    background: #f1f5f9;
}
.single-avatar-container {
    display: flex;
    align-items: center;
    gap: 12px;
}
.avatar-display-btn {
    width: 64px;
    height: 64px;
    border-radius: 16px;
    border: 2px solid var(--border);
    background: var(--surface);
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: transform 0.2s, box-shadow 0.2s;
}
.avatar-display-btn:hover {
    transform: scale(1.05);
    box-shadow: 0 4px 12px rgba(0,0,0,0.1);
}
.avatar-display-btn:active {
    transform: scale(0.98);
}
.emoji-avatar-large {
    font-size: 36px;
    width: 100%;
    height: 100%;
    border-radius: 14px;
    display: flex;
    align-items: center;
    justify-content: center;
}
.emoji-avatar-bubble {
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 20px;
    border-radius: 12px;
}
.avatar-options-hidden {
    display: none;
}
.avatar-actions {
    display: flex;
    justify-content: flex-start;
    gap: 8px;
    align-items: center;
}
.tip-card {
    background: var(--surface);
    border-radius: 16px;
    padding: 16px;
    border: 1px solid var(--border);
    box-shadow: 0 10px 30px rgba(15,23,42,0.05);
}
.mini-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(230px, 1fr));
    gap: 16px;
    margin: 0 auto;
    width: min(1100px, 100%);
    padding: 0 4px 10px;
}

/* Landing */
.landing-shell {
    width: min(980px, 100%);
    margin: 0 auto;
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
    gap: 22px;
    align-items: center;
}
.intro h1 { margin: 10px 0 12px; font-size: 32px; }
.mini-points {
    display: flex;
    gap: 10px;
    flex-wrap: wrap;
}
.hero-card { width: 100%; }
.card-title { margin: 0 0 8px; }

/* Chat page */
.chat-shell {
    max-width: 1100px;
    margin: 0 auto;
    padding: 0;
    display: flex;
    flex-direction: column;
    gap: 0;
    height: 100vh;
    height: 100dvh; /* Use dynamic viewport height for mobile */
    box-sizing: border-box;
    overflow: hidden;
}
.topbar {
    display: flex;
    justify-content: space-between;
    align-items: center;
    gap: 16px;
    flex-shrink: 0;
    padding: 12px 18px;
    margin: 12px 12px 0 12px;
    border-radius: 18px;
}
.room-id-row {
    display: flex;
    align-items: center;
    gap: 8px;
    flex-wrap: wrap;
    font-weight: 700;
}
.room-id-link {
    text-decoration: none;
    color: inherit;
    cursor: pointer;
    transition: opacity 0.2s;
}
.room-id-link:hover {
    opacity: 0.7;
}
.topbar-actions { display: flex; gap: 8px; align-items: center; }
.icon-btn {
    width: 42px;
    height: 42px;
    border-radius: 12px;
    display: grid;
    place-items: center;
    border: 1px solid var(--border);
    background: var(--surface);
    font-size: 18px;
    padding: 0;
    color: var(--text);
}
:root[data-theme="dark"] .icon-btn,
body[data-theme="dark"] .icon-btn {
    color: #e2e8f0;
    border-color: #334155;
}
.theme-icon {
    width: 20px;
    height: 20px;
    stroke: currentColor;
}
.theme-icon-path {
    transition: d 0.3s ease;
}
.lang-chips { 
    display: flex; 
    gap: 8px; 
    flex-wrap: nowrap; 
    padding-top: 8px;
}
.chip {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 6px 10px;
    border-radius: 6px;
    background: var(--chip-bg);
    color: var(--chip-text);
    font-weight: 700;
    font-size: 12px;
    min-width: 3.5em;
    text-align: center;
    white-space: nowrap;
}
.chip-muted {
    background: rgba(241,245,249,0.7);
    color: var(--muted);
    font-weight: 600;
}
:root[data-theme="dark"] .chip-muted,
body[data-theme="dark"] .chip-muted {
    background: rgba(59, 130, 246, 0.2);
    color: #93c5fd;
    border: 1px solid rgba(59, 130, 246, 0.3);
}
.profile-card { padding: 14px 16px; }
.profile-box {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
    gap: 12px;
    align-items: start;
}
.profile-block { display: flex; flex-direction: column; gap: 6px; }
.profile-block.helper { justify-content: center; }
.profile-actions { display: flex; gap: 8px; }
.name-row {
    display: flex;
    gap: 8px;
    align-items: center;
}
.chat-panel {
    flex: 1;
    min-height: 0;
    overflow-y: auto;
    overflow-x: hidden;
    background: var(--surface);
    border-radius: 18px;
    border: 1px solid var(--border);
    padding: 14px;
    margin: 12px;
    box-shadow: inset 0 1px 0 var(--border);
}
#messages {
    display: flex;
    flex-direction: column;
    gap: 12px;
}
.side-panel {
    border-radius: 16px;
    border: 1px solid var(--border);
    background: var(--surface);
    padding: 14px 16px;
    box-shadow: var(--shadow);
}
.side-title { font-weight: 700; margin-bottom: 6px; }
.side-item { margin-bottom: 10px; }
.side-value { font-weight: 700; letter-spacing: 0.5px; }
.side-tips { margin: 6px 0 0; padding-left: 18px; color: var(--muted); }

.bubble-row {
    display: flex;
    gap: 10px;
    align-items: flex-end;
}
.bubble-row.left { flex-direction: row; }
.bubble-row.right { flex-direction: row-reverse; }
.bubble-avatar {
    width: 42px;
    height: 42px;
    border-radius: 12px;
    object-fit: cover;
}
.avatar.placeholder {
    display: grid;
    place-items: center;
    background: #e2e8f0;
    color: #475569;
    font-weight: 800;
}
:root[data-theme="dark"] .avatar.placeholder,
body[data-theme="dark"] .avatar.placeholder {
    background: #1e293b;
    color: #e2e8f0;
}
.bubble {
    max-width: 75%;
    background: var(--bubble-other);
    border-radius: 14px;
    padding: 10px 12px;
    border: 1px solid var(--border);
    box-shadow: 0 6px 20px rgba(15,23,42,0.05);
}
.bubble-row.right .bubble { background: var(--bubble-self); border-color: #bfdbfe; }
.bubble-meta { 
    display: flex; 
    gap: 8px; 
    align-items: baseline; 
    justify-content: space-between;
}
.bubble-time {
    margin-left: auto;
}
.bubble-text { 
    margin: 6px 0; 
    white-space: pre-wrap;
    user-select: text;
    cursor: text;
}
.translation-block { 
    border-top: 2px solid var(--border); 
    padding-top: 8px; 
    margin-top: 8px;
}
:root[data-theme="dark"] .translation-block,
body[data-theme="dark"] .translation-block {
    border-top: 2px solid rgba(148, 163, 184, 0.5);
}
.translation-line { 
    display: flex; 
    gap: 8px; 
    align-items: baseline; 
    margin-top: 4px; 
    flex-wrap: nowrap;
}
.translation-lang {
    flex-shrink: 0;
    min-width: 5em;
    max-width: 5em;
    text-align: center;
    display: inline-block;
}
.translation-text {
    color: var(--muted);
    font-size: 0.9em;
    line-height: 1.4;
    flex: 1;
    opacity: 0.85;
}
.composer {
    display: flex;
    align-items: flex-end;
    gap: 12px;
    padding: 12px 18px;
    margin: 0 12px 12px;
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: 18px;
    flex-shrink: 0;
    position: relative;
    z-index: 10;
    box-shadow: var(--shadow);
}
.composer textarea {
    flex: 1;
    resize: none;
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: 4px;
    padding: 12px 14px;
    min-height: 44px;
    max-height: 120px;
    font-size: 16px; /* 16px prevents auto-zoom on mobile */
    line-height: 1.4;
}
.composer textarea:focus {
    outline: none;
    border-color: var(--primary);
}
.send-btn {
    width: 48px;
    height: 48px;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 0;
    background: linear-gradient(135deg, var(--primary), var(--primary-strong));
    color: #fff;
    border: none;
    border-radius: 50%;
    cursor: pointer;
    transition: transform 0.2s, box-shadow 0.2s;
    box-shadow: 0 2px 8px rgba(37, 99, 235, 0.3);
    flex-shrink: 0;
    -webkit-tap-highlight-color: transparent;
    touch-action: manipulation;
}
.send-btn:hover {
    transform: translateY(-1px);
    box-shadow: 0 4px 12px rgba(37, 99, 235, 0.4);
}
.send-btn:active {
    transform: translateY(0);
}
.send-btn:focus {
    outline: none;
}
.send-icon {
    width: 20px;
    height: 20px;
    stroke: currentColor;
    transition: transform 0.2s;
}
.send-btn:hover .send-icon {
    transform: translateX(1px);
}
.messages::-webkit-scrollbar,
.chat-panel::-webkit-scrollbar { width: 8px; }
.messages::-webkit-scrollbar-thumb,
.chat-panel::-webkit-scrollbar-thumb {
    background: #cbd5e1;
    border-radius: 999px;
}

.hero-actions {
    display: flex;
    gap: 16px;
    justify-content: center;
    flex-wrap: wrap;
}
.my-rooms-container {
    width: 100%;
    max-width: 600px;
    animation: fadeIn 0.3s ease;
}
.my-rooms-list {
    max-height: 400px;
    overflow-y: auto;
    margin: 16px 0;
    padding: 2px 0;
}
.room-item {
    padding: 12px;
    border: 1px solid var(--border);
    border-radius: 12px;
    margin-bottom: 8px;
    background: var(--surface);
    cursor: pointer;
    transition: all 0.2s ease;
    position: relative;
}
.room-item:hover {
    background: rgba(37, 99, 235, 0.05);
    border-color: var(--primary);
    transform: translateY(-1px);
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.1);
}
:root[data-theme="dark"] .room-item:hover,
body[data-theme="dark"] .room-item:hover {
    background: rgba(59, 130, 246, 0.1);
    border-color: var(--primary);
}
.room-item:active {
    transform: translateY(0);
}
.room-item-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 6px;
}
.room-item-id {
    font-weight: 700;
}
.room-item-meta {
    font-size: 12px;
}
.delete-room-btn {
    padding: 6px 12px;
    background: transparent;
    color: #ef4444;
    border: 1px solid #ef4444;
    border-radius: 6px;
    font-size: 13px;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.2s;
    z-index: 1;
    position: relative;
}
.delete-room-btn:hover {
    background: #ef4444;
    color: #fff;
}
.delete-room-btn:active {
    transform: translateY(1px);
}
.create-btn {
    margin-top: 24px;
}
.modal-overlay {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: rgba(0, 0, 0, 0.5);
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 1000;
    backdrop-filter: blur(4px);
}
.modal-content {
    max-width: 400px;
    width: 90%;
    animation: slideUp 0.3s ease;
}
@keyframes slideUp {
    from {
        opacity: 0;
        transform: translateY(20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}
.modal-form {
    display: flex;
    flex-direction: column;
    gap: 12px;
    margin-top: 16px;
}
.custom-link-hint {
    display: flex;
    flex-direction: column;
    gap: 4px;
}

@media (max-width: 960px) {
    .landing-hero h1 { font-size: 36px; }
    .landing-subtitle { font-size: 16px; }
    .hero-actions { flex-direction: column; }
    .hero-actions .large-btn { width: 100%; }
    .chat-shell {
        padding: 0;
        height: 100vh;
        height: 100dvh;
    }
    .topbar {
        padding: 10px 14px;
        margin: 8px 8px 0 8px;
        border-radius: 12px;
    }
    .chat-panel {
        margin: 8px;
        border-radius: 12px;
    }
    .composer {
        padding: 10px 14px;
        margin: 0 8px 8px;
        border-radius: 12px;
    }
    .inline-input { flex-direction: column; align-items: stretch; }
}