/* Fluent Design System Variables */
:root {
    --bg-primary: #faf9f8;
    --bg-secondary: #f3f2f1;
    --bg-card: #ffffff;
    --text-primary: #323130;
    --text-secondary: #605e5c;
    --text-muted: #a19f9d;
    --border-color: #edebe9;
    --accent: #0078d4;
    --accent-hover: #106ebe;
    --accent-light: #deecf9;
    --shadow-4: 0 1.6px 3.6px 0 rgba(0,0,0,0.132), 0 0.3px 0.9px 0 rgba(0,0,0,0.108);
    --shadow-8: 0 3.2px 7.2px 0 rgba(0,0,0,0.132), 0 0.6px 1.8px 0 rgba(0,0,0,0.108);
    --shadow-16: 0 6.4px 14.4px 0 rgba(0,0,0,0.132), 0 1.2px 3.6px 0 rgba(0,0,0,0.108);
    --shadow-64: 0 25.6px 57.6px 0 rgba(0,0,0,0.22), 0 4.8px 14.4px 0 rgba(0,0,0,0.18);
    --code-bg: #f3f2f1;
    --radius: 8px;
}

[data-theme="dark"] {
    --bg-primary: #1b1a19;
    --bg-secondary: #252423;
    --bg-card: #292827;
    --text-primary: #f3f2f1;
    --text-secondary: #d2d0ce;
    --text-muted: #979593;
    --border-color: #3b3a39;
    --accent: #2899f5;
    --accent-hover: #5eb3f7;
    --accent-light: #0a2e4a;
    --shadow-4: 0 1.6px 3.6px 0 rgba(0,0,0,0.4), 0 0.3px 0.9px 0 rgba(0,0,0,0.32);
    --shadow-8: 0 3.2px 7.2px 0 rgba(0,0,0,0.4), 0 0.6px 1.8px 0 rgba(0,0,0,0.32);
    --shadow-16: 0 6.4px 14.4px 0 rgba(0,0,0,0.4), 0 1.2px 3.6px 0 rgba(0,0,0,0.32);
    --shadow-64: 0 25.6px 57.6px 0 rgba(0,0,0,0.55), 0 4.8px 14.4px 0 rgba(0,0,0,0.45);
    --code-bg: #323130;
}

/* Warning banner */
.warning-banner {
    background: #dc3545;
    color: white;
    text-align: center;
    padding: 0.5rem 1rem;
    font-size: 0.85rem;
    font-weight: 500;
}

/* Reset and base */
* {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, sans-serif;
    background: var(--bg-primary);
    color: var(--text-primary);
    line-height: 1.6;
    transition: background 0.3s, color 0.3s;
}

/* Header */
header {
    background: var(--bg-card);
    color: var(--text-primary);
    padding: 1rem 2rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
    position: sticky;
    top: 0;
    z-index: 100;
    box-shadow: var(--shadow-4);
    border-bottom: 3px solid var(--accent);
}

.header-content h1 {
    font-size: 1.5rem;
    font-weight: 600;
    color: var(--accent);
}

.subtitle {
    color: var(--text-secondary);
    font-size: 0.85rem;
}

#theme-toggle {
    background: var(--bg-secondary);
    border: 1px solid var(--border-color);
    border-radius: var(--radius);
    width: 40px;
    height: 40px;
    cursor: pointer;
    font-size: 1.2rem;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: all 0.1s ease;
}

#theme-toggle:hover {
    background: var(--accent-light);
    border-color: var(--accent);
}

.sun, .moon {
    position: absolute;
}

[data-theme="dark"] .sun { display: none; }
[data-theme="dark"] .moon { display: block; }
:root .sun { display: block; }
:root .moon { display: none; }

/* Main content */
main {
    max-width: 1400px;
    margin: 0 auto;
    padding: 1.5rem;
}

/* Controls */
.controls {
    display: flex;
    flex-wrap: wrap;
    gap: 1rem;
    margin-bottom: 1.5rem;
    align-items: center;
}

.search-box {
    position: relative;
    flex: 1;
    min-width: 250px;
}

.search-box input {
    width: 100%;
    padding: 0.625rem 1rem 0.625rem 2.5rem;
    border: 1px solid var(--border-color);
    border-radius: var(--radius);
    font-size: 0.875rem;
    background: var(--bg-card);
    color: var(--text-primary);
    transition: all 0.1s ease;
}

.search-box input:hover {
    border-color: var(--text-muted);
}

.search-box input:focus {
    outline: none;
    border-color: var(--accent);
    border-bottom-width: 2px;
}

.search-icon {
    position: absolute;
    left: 0.75rem;
    top: 50%;
    transform: translateY(-50%);
    color: var(--text-muted);
}

.filters {
    display: flex;
    gap: 0.5rem;
    flex-wrap: wrap;
}

.filters select {
    padding: 0.625rem 2rem 0.625rem 1rem;
    border: 1px solid var(--border-color);
    border-radius: var(--radius);
    font-size: 0.875rem;
    background: var(--bg-card);
    color: var(--text-primary);
    cursor: pointer;
    min-width: 140px;
    transition: all 0.1s ease;
    appearance: none;
    background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='12' height='12' viewBox='0 0 12 12'%3E%3Cpath fill='%23605e5c' d='M2.5 4.5L6 8l3.5-3.5z'/%3E%3C/svg%3E");
    background-repeat: no-repeat;
    background-position: right 0.75rem center;
}

.filters select:hover {
    border-color: var(--text-muted);
}

.filters select:focus {
    outline: none;
    border-color: var(--accent);
    border-bottom-width: 2px;
}

.stats {
    color: var(--text-secondary);
    font-size: 0.9rem;
    white-space: nowrap;
}

/* Sessions grid */
.sessions-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(350px, 1fr));
    gap: 1rem;
}

.session-card {
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: var(--radius);
    padding: 1.25rem;
    cursor: pointer;
    transition: all 0.1s ease;
    box-shadow: var(--shadow-4);
}

.session-card:hover {
    box-shadow: var(--shadow-8);
    border-color: var(--accent);
    background: var(--accent-light);
}

.session-card-header {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    margin-bottom: 0.5rem;
}

.session-code {
    display: inline-block;
    background: var(--accent);
    color: white;
    padding: 0.2rem 0.5rem;
    border-radius: 4px;
    font-size: 0.7rem;
    font-weight: 600;
    letter-spacing: 0.02em;
}

.slides-icon {
    font-size: 1rem;
    opacity: 0.7;
    cursor: help;
}

.session-title {
    font-size: 1.1rem;
    font-weight: 600;
    margin-bottom: 0.5rem;
    color: var(--text-primary);
    display: -webkit-box;
    -webkit-line-clamp: 2;
    -webkit-box-orient: vertical;
    overflow: hidden;
}

.session-meta {
    display: flex;
    flex-wrap: wrap;
    gap: 0.5rem;
    margin-top: 0.75rem;
}

.meta-tag {
    font-size: 0.75rem;
    color: var(--text-secondary);
    background: var(--bg-secondary);
    padding: 0.2rem 0.6rem;
    border-radius: 12px;
    border: 1px solid var(--border-color);
}

.session-speakers {
    font-size: 0.85rem;
    color: var(--text-secondary);
    margin-top: 0.5rem;
}

/* Modal */
.modal {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.6);
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 1000;
    padding: 1rem;
}

.modal.hidden {
    display: none;
}

.modal-content {
    background: var(--bg-card);
    border-radius: var(--radius);
    max-width: 900px;
    max-height: 90vh;
    width: 100%;
    overflow-y: auto;
    position: relative;
    box-shadow: var(--shadow-64);
}

.modal-close {
    position: sticky;
    top: 0;
    float: right;
    background: var(--bg-secondary);
    border: none;
    font-size: 1.5rem;
    width: 40px;
    height: 40px;
    border-radius: 50%;
    cursor: pointer;
    color: var(--text-primary);
    margin: 1rem;
    z-index: 10;
}

.modal-close:hover {
    background: var(--border-color);
}

#modal-body {
    padding: 0 2rem 2rem;
}

#modal-body h1 {
    font-size: 1.75rem;
    margin-bottom: 1rem;
    color: var(--text-primary);
}

#modal-body h2 {
    font-size: 1.25rem;
    margin: 1.5rem 0 0.75rem;
    color: var(--text-primary);
    border-bottom: 1px solid var(--border-color);
    padding-bottom: 0.5rem;
}

#modal-body h3 {
    font-size: 1.1rem;
    margin: 1rem 0 0.5rem;
    color: var(--text-primary);
}

#modal-body p {
    margin-bottom: 1rem;
    color: var(--text-secondary);
}

#modal-body ul, #modal-body ol {
    margin: 0.5rem 0 1rem 1.5rem;
    color: var(--text-secondary);
}

#modal-body li {
    margin-bottom: 0.5rem;
}

#modal-body code {
    background: var(--code-bg);
    padding: 0.2rem 0.4rem;
    border-radius: 4px;
    font-family: 'Consolas', 'Monaco', monospace;
    font-size: 0.9em;
}

#modal-body pre {
    background: var(--code-bg);
    padding: 1rem;
    border-radius: 8px;
    overflow-x: auto;
    margin: 1rem 0;
}

#modal-body pre code {
    background: none;
    padding: 0;
}

#modal-body strong {
    color: var(--text-primary);
}

/* Session header in modal */
.session-header {
    margin-bottom: 1.5rem;
    padding-bottom: 1rem;
    border-bottom: 2px solid var(--accent);
}

.session-header .session-code {
    font-size: 0.9rem;
    margin-bottom: 0.75rem;
}

.session-header .date {
    color: var(--text-muted);
    font-size: 0.9rem;
}

.download-slides-btn {
    display: inline-block;
    margin-top: 0.75rem;
    padding: 0.5rem 1rem;
    background: var(--accent);
    color: white;
    text-decoration: none;
    border-radius: var(--radius);
    font-size: 0.875rem;
    font-weight: 500;
    transition: background 0.1s ease;
}

.download-slides-btn:hover {
    background: var(--accent-hover);
    text-decoration: none;
}

/* Footer */
footer {
    text-align: center;
    padding: 2rem;
    color: var(--text-muted);
    font-size: 0.85rem;
    border-top: 1px solid var(--border-color);
    margin-top: 2rem;
}

footer a {
    color: var(--accent);
    text-decoration: none;
    font-weight: 500;
}

footer a:hover {
    text-decoration: underline;
}

/* Loading state */
.loading {
    text-align: center;
    padding: 3rem;
    color: var(--text-secondary);
}

/* Empty state */
.no-results {
    text-align: center;
    padding: 3rem;
    color: var(--text-secondary);
}

/* Info Toggles */
.info-toggles {
    display: flex;
    flex-wrap: wrap;
    gap: 0.5rem;
    margin-bottom: 1rem;
    align-items: center;
}

/* Download Buttons */
.download-buttons {
    display: flex;
    gap: 0.5rem;
    margin-left: auto;
}

.download-btn {
    display: inline-flex;
    align-items: center;
    gap: 0.4rem;
    padding: 0.5rem 1rem;
    background: var(--accent);
    border: none;
    border-radius: var(--radius);
    color: white;
    font-size: 0.875rem;
    font-weight: 500;
    cursor: pointer;
    transition: all 0.1s ease;
    text-decoration: none;
    box-shadow: var(--shadow-4);
}

.download-btn:hover {
    background: var(--accent-hover);
    box-shadow: var(--shadow-8);
}

.download-icon {
    font-size: 1rem;
}

/* Slides Modal */
.slides-modal-body {
    padding: 0 2rem 2rem;
}

.slides-modal-body h2 {
    font-size: 1.5rem;
    margin-bottom: 1rem;
    color: var(--text-primary);
}

.slides-modal-body > p {
    color: var(--text-secondary);
    margin-bottom: 1.5rem;
}

.slides-options {
    display: grid;
    gap: 1.5rem;
    margin-bottom: 1.5rem;
}

.slides-option {
    background: var(--bg-secondary);
    padding: 1.25rem;
    border-radius: var(--radius);
    border: 1px solid var(--border-color);
}

.slides-option h3 {
    font-size: 1.1rem;
    color: var(--text-primary);
    margin-bottom: 0.5rem;
}

.slides-option p {
    color: var(--text-secondary);
    font-size: 0.9rem;
    margin-bottom: 0.75rem;
}

.slides-option pre {
    background: var(--code-bg);
    padding: 0.75rem 1rem;
    border-radius: 6px;
    overflow-x: auto;
    margin: 0;
}

.slides-option code {
    font-family: 'Consolas', 'Monaco', monospace;
    font-size: 0.9rem;
    color: var(--text-primary);
}

.slides-option a {
    color: var(--accent);
    text-decoration: none;
    font-weight: 500;
}

.slides-option a:hover {
    text-decoration: underline;
}

.script-note {
    font-size: 0.8rem;
    color: var(--text-muted);
    margin-top: 0.5rem;
    margin-bottom: 0;
}

.slides-stats {
    text-align: center;
    color: var(--text-muted);
    font-size: 0.9rem;
    padding-top: 1rem;
    border-top: 1px solid var(--border-color);
}

.slides-stats span {
    font-weight: 600;
    color: var(--accent);
}

.info-toggle {
    padding: 0.5rem 1rem;
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: var(--radius);
    color: var(--text-secondary);
    font-size: 0.875rem;
    cursor: pointer;
    transition: all 0.1s ease;
    box-shadow: var(--shadow-4);
}

.info-toggle:hover {
    background: var(--accent-light);
    border-color: var(--accent);
    color: var(--accent);
}

.info-toggle.active {
    background: var(--accent);
    border-color: var(--accent);
    color: white;
    box-shadow: var(--shadow-8);
}

/* Info Panels */
.info-panel {
    margin-bottom: 1.5rem;
    padding: 1.5rem;
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: var(--radius);
    box-shadow: var(--shadow-4);
    animation: slideDown 0.15s ease-out;
}

.info-panel.hidden {
    display: none;
}

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

/* Stats Grid */
.stats-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(150px, 1fr));
    gap: 1rem;
}

.stat-card {
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: 8px;
    padding: 1rem;
    text-align: center;
}

.stat-number {
    display: block;
    font-size: 2rem;
    font-weight: 700;
    color: var(--accent);
}

.stat-label {
    display: block;
    font-size: 0.85rem;
    color: var(--text-secondary);
    margin-top: 0.25rem;
}

/* About Content */
.about-content {
    display: grid;
    gap: 1.5rem;
}

.about-block h3 {
    font-size: 1.1rem;
    color: var(--text-primary);
    margin-bottom: 0.75rem;
}

.about-block ol,
.about-block ul {
    margin-left: 1.5rem;
    color: var(--text-secondary);
}

.about-block li {
    margin-bottom: 0.5rem;
    line-height: 1.6;
}

.about-block p {
    color: var(--text-secondary);
    line-height: 1.6;
}

.about-block a {
    color: var(--accent);
    text-decoration: none;
}

.about-block a:hover {
    text-decoration: underline;
}

/* Responsive */
@media (max-width: 768px) {
    header {
        padding: 1rem;
    }

    .header-content h1 {
        font-size: 1.25rem;
    }

    .controls {
        flex-direction: column;
    }

    .search-box {
        width: 100%;
    }

    .filters {
        width: 100%;
    }

    .filters select {
        flex: 1;
    }

    .sessions-grid {
        grid-template-columns: 1fr;
    }

    .modal-content {
        border-radius: 12px 12px 0 0;
        max-height: 95vh;
        margin-top: auto;
    }
}