:root {
    --bg: #ffffff;
    --bg-secondary: #f5f5f5;
    --bg-card: #ffffff;
    --text: #1a1a1a;
    --text-secondary: #666;
    --border: #e0e0e0;
    --accent: #2688eb;
    --shadow: 0 2px 8px rgba(0,0,0,0.08);
}

[data-theme="dark"] {
    --bg: #111111;
    --bg-secondary: #1e1e1e;
    --bg-card: #242424;
    --text: #ffffff;
    --text-secondary: #999;
    --border: #333;
    --shadow: 0 2px 8px rgba(0,0,0,0.4);
}

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

body {
    background: var(--bg);
    color: var(--text);
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    transition: background 0.3s, color 0.3s;
    min-height: 100vh;
}

/* HEADER */
header {
    background: var(--bg-secondary);
    border-bottom: 1px solid var(--border);
    padding: 0 24px;
    height: 60px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    position: sticky;
    top: 0;
    z-index: 100;
}

.logo { font-size: 18px; font-weight: 700; color: var(--accent); text-decoration: none; }

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

.theme-btn {
    background: none;
    border: 1px solid var(--border);
    color: var(--text);
    padding: 6px 14px;
    border-radius: 20px;
    cursor: pointer;
    font-size: 13px;
    transition: all 0.2s;
}
.theme-btn:hover { background: var(--border); }

.logout-btn {
    background: none;
    border: 1px solid var(--border);
    color: var(--text-secondary);
    padding: 6px 14px;
    border-radius: 20px;
    cursor: pointer;
    font-size: 13px;
    text-decoration: none;
    transition: all 0.2s;
}
.logout-btn:hover { color: var(--text); background: var(--border); }

/* LOGIN PAGE */
.login-page {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    min-height: calc(100vh - 60px);
    gap: 16px;
    padding: 24px;
}
.login-page h2 { font-size: 32px; font-weight: 700; }
.login-page p { color: var(--text-secondary); font-size: 16px; }
#vk-login { width: 360px; margin-top: 8px; }

/* VIDEOS PAGE */
.videos-page { padding: 24px; max-width: 1400px; margin: 0 auto; }

.videos-toolbar {
    display: flex;
    align-items: center;
    justify-content: space-between;
    margin-bottom: 24px;
    flex-wrap: wrap;
    gap: 12px;
}
.videos-toolbar h2 { font-size: 22px; font-weight: 700; }

.sort-controls { display: flex; gap: 8px; }

.sort-btn {
    background: var(--bg-secondary);
    border: 1px solid var(--border);
    color: var(--text-secondary);
    padding: 7px 16px;
    border-radius: 20px;
    cursor: pointer;
    font-size: 13px;
    transition: all 0.2s;
}
.sort-btn:hover, .sort-btn.active {
    background: var(--accent);
    border-color: var(--accent);
    color: #fff;
}

/* VIDEO GRID */
.video-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
    gap: 20px;
}

.video-card {
    background: var(--bg-card);
    border-radius: 12px;
    overflow: hidden;
    box-shadow: var(--shadow);
    cursor: pointer;
    transition: transform 0.2s, box-shadow 0.2s;
    text-decoration: none;
    color: inherit;
    display: block;
}
.video-card:hover { transform: translateY(-4px); box-shadow: 0 8px 24px rgba(0,0,0,0.15); }

.video-thumb {
    width: 100%;
    aspect-ratio: 16/9;
    object-fit: cover;
    background: var(--bg-secondary);
    display: block;
}
.video-thumb-placeholder {
    width: 100%;
    aspect-ratio: 16/9;
    background: var(--bg-secondary);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 40px;
}

.video-info { padding: 12px; }
.video-title {
    font-size: 14px;
    font-weight: 600;
    line-height: 1.4;
    margin-bottom: 6px;
    display: -webkit-box;
    -webkit-line-clamp: 2;
    -webkit-box-orient: vertical;
    overflow: hidden;
}
.video-meta { display: flex; gap: 12px; font-size: 12px; color: var(--text-secondary); }

/* VIDEO PLAYER PAGE */
.player-page { padding: 24px; max-width: 1100px; margin: 0 auto; }

.back-btn {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    color: var(--text-secondary);
    text-decoration: none;
    font-size: 14px;
    margin-bottom: 16px;
    transition: color 0.2s;
}
.back-btn:hover { color: var(--accent); }

.player-wrapper {
    width: 100%;
    aspect-ratio: 16/9;
    background: #000;
    border-radius: 12px;
    overflow: hidden;
    margin-bottom: 20px;
}
.player-wrapper iframe { width: 100%; height: 100%; border: none; }

.video-details h1 { font-size: 22px; font-weight: 700; margin-bottom: 10px; }
.video-details .meta { display: flex; gap: 20px; color: var(--text-secondary); font-size: 14px; }

/* EMPTY STATE */
.empty { text-align: center; padding: 80px 24px; color: var(--text-secondary); }
.empty p { font-size: 16px; margin-top: 8px; }

/* LOADER */
.loader-overlay {
    position: fixed;
    inset: 0;
    background: var(--bg);
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    z-index: 999;
    gap: 20px;
    transition: opacity 0.5s;
}
.loader-spinner {
    width: 48px;
    height: 48px;
    border: 4px solid var(--border);
    border-top-color: var(--accent);
    border-radius: 50%;
    animation: spin 0.8s linear infinite;
}
@keyframes spin { to { transform: rotate(360deg); } }
.loader-text {
    font-size: 18px;
    font-weight: 600;
    text-align: center;
}
.loader-sub {
    font-size: 14px;
    color: var(--text-secondary);
    text-align: center;
    max-width: 300px;
}