/* =============================================================
   academy.css — FPV Academy Educational Hub Styles
   All classes prefixed acad- to avoid collisions with other pages.
   Uses CSS variables from base.css exclusively.
   ============================================================= */

/* --- Hero Section --- */
.acad-hero {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 40px 48px;
    background: var(--bg-panel);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-lg);
    box-shadow: var(--card-shadow);
    position: relative;
    overflow: hidden;
    margin-bottom: 32px;
}

.acad-hero::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 4px;
    background: linear-gradient(90deg, var(--accent-purple), var(--accent-blue), var(--accent-cyan));
}

.acad-hero-text {
    max-width: 640px;
    z-index: 1;
}

.acad-hero-title {
    font-size: 36px;
    font-weight: 800;
    color: var(--text-main);
    margin: 0 0 12px 0;
    line-height: 1.2;
}

.acad-hero-accent {
    background: linear-gradient(135deg, var(--accent-purple), var(--accent-blue));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.acad-hero-subtitle {
    font-size: 16px;
    line-height: 1.6;
    color: var(--text-muted);
    margin: 0 0 20px 0;
}

.acad-hero-cta {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 10px 24px;
    background: linear-gradient(135deg, var(--accent-purple), var(--accent-blue));
    color: white;
    border: none;
    border-radius: var(--radius-sm);
    font-size: 14px;
    font-weight: 600;
    cursor: pointer;
    text-decoration: none;
    transition: transform 0.2s ease, box-shadow 0.2s ease;
}

.acad-hero-cta:hover {
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(139, 92, 246, 0.35);
}

.acad-hero-cta i {
    font-size: 18px;
    transition: transform 0.2s ease;
}

.acad-hero-cta:hover i {
    transform: translateY(2px);
}

.acad-hero-graphic {
    display: flex;
    align-items: center;
    justify-content: center;
    opacity: 0.10;
    position: absolute;
    right: 40px;
    top: 50%;
    transform: translateY(-50%);
}

.acad-hero-graphic i {
    font-size: 160px;
    color: var(--accent-purple);
}

[data-theme="dark"] .acad-hero-graphic {
    opacity: 0.06;
}

/* --- Topic Cards Grid --- */
.acad-section {
    margin-bottom: 40px;
}

.acad-section-title {
    font-size: 20px;
    font-weight: 700;
    color: var(--text-main);
    margin: 0 0 20px 0;
    padding-bottom: 12px;
    border-bottom: 2px solid var(--border-color);
    display: flex;
    align-items: center;
    gap: 10px;
}

.acad-section-title i {
    color: var(--accent-purple);
    font-size: 22px;
}

.acad-topics-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
    gap: 20px;
}

.acad-topic-card {
    position: relative;
    display: flex;
    flex-direction: column;
    background: var(--bg-panel);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    padding: 24px 20px 20px;
    box-shadow: var(--card-shadow);
    cursor: pointer;
    transition: all 0.3s cubic-bezier(0.25, 0.8, 0.25, 1);
    overflow: hidden;
}

.acad-topic-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 4px;
    background: linear-gradient(90deg, var(--accent-purple), var(--accent-blue));
    opacity: 0;
    transition: opacity 0.3s ease;
}

.acad-topic-card:hover {
    transform: translateY(-4px);
    box-shadow: var(--card-shadow-hover);
    border-color: var(--border-hover);
}

.acad-topic-card:hover::before {
    opacity: 1;
}

.acad-topic-card:hover .acad-card-read-more {
    color: var(--accent-purple);
}

.acad-topic-card:hover .acad-card-read-more i {
    transform: translateX(4px);
}

/* --- Card Icon --- */
.acad-card-icon {
    width: 48px;
    height: 48px;
    border-radius: var(--radius-sm);
    display: flex;
    align-items: center;
    justify-content: center;
    margin-bottom: 14px;
    font-size: 24px;
    transition: transform 0.3s ease;
}

.acad-topic-card:hover .acad-card-icon {
    transform: scale(1.08);
}

/* Per-card accent colors */
.acad-topic-card[data-accent="purple"] .acad-card-icon {
    background: rgba(139, 92, 246, 0.1);
    color: var(--accent-purple);
}
.acad-topic-card[data-accent="red"] .acad-card-icon {
    background: rgba(34, 211, 238, 0.1);
    color: var(--accent-red);
}
.acad-topic-card[data-accent="blue"] .acad-card-icon {
    background: rgba(2, 132, 199, 0.1);
    color: var(--accent-blue);
}
.acad-topic-card[data-accent="cyan"] .acad-card-icon {
    background: rgba(6, 182, 212, 0.1);
    color: var(--accent-cyan);
}
.acad-topic-card[data-accent="amber"] .acad-card-icon {
    background: rgba(245, 158, 11, 0.1);
    color: #f59e0b;
}
.acad-topic-card[data-accent="green"] .acad-card-icon {
    background: rgba(34, 197, 94, 0.1);
    color: var(--accent-green);
}
.acad-topic-card[data-accent="slate"] .acad-card-icon {
    background: rgba(100, 116, 139, 0.1);
    color: var(--text-muted);
}

/* Dark mode accent backgrounds */
[data-theme="dark"] .acad-topic-card[data-accent="purple"] .acad-card-icon {
    background: rgba(139, 92, 246, 0.15);
}
[data-theme="dark"] .acad-topic-card[data-accent="red"] .acad-card-icon {
    background: rgba(255, 59, 48, 0.15);
}
[data-theme="dark"] .acad-topic-card[data-accent="blue"] .acad-card-icon {
    background: rgba(2, 132, 199, 0.15);
}
[data-theme="dark"] .acad-topic-card[data-accent="cyan"] .acad-card-icon {
    background: rgba(6, 182, 212, 0.15);
}
[data-theme="dark"] .acad-topic-card[data-accent="amber"] .acad-card-icon {
    background: rgba(245, 158, 11, 0.15);
}
[data-theme="dark"] .acad-topic-card[data-accent="green"] .acad-card-icon {
    background: rgba(34, 197, 94, 0.15);
}
[data-theme="dark"] .acad-topic-card[data-accent="slate"] .acad-card-icon {
    background: rgba(100, 116, 139, 0.15);
}

/* --- Card Body --- */
.acad-card-body {
    flex: 1;
}

.acad-card-title {
    font-size: 16px;
    font-weight: 700;
    color: var(--text-main);
    margin: 0 0 6px 0;
}

.acad-card-desc {
    font-size: 13px;
    line-height: 1.5;
    color: var(--text-muted);
    margin: 0;
}

.acad-card-read-more {
    display: inline-flex;
    align-items: center;
    gap: 4px;
    margin-top: 14px;
    font-size: 13px;
    font-weight: 600;
    color: var(--text-faint);
    transition: color 0.2s ease;
}

.acad-card-read-more i {
    font-size: 16px;
    transition: transform 0.2s ease;
}

/* --- Article Sections --- */
.acad-articles {
    display: flex;
    flex-direction: column;
    gap: 16px;
    margin-bottom: 40px;
}

.acad-article {
    background: var(--bg-panel);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    box-shadow: var(--card-shadow);
    overflow: hidden;
}

.acad-article[data-accent="purple"] { border-left: 4px solid var(--accent-purple); }
.acad-article[data-accent="red"] { border-left: 4px solid var(--accent-red); }
.acad-article[data-accent="blue"] { border-left: 4px solid var(--accent-blue); }
.acad-article[data-accent="cyan"] { border-left: 4px solid var(--accent-cyan); }
.acad-article[data-accent="amber"] { border-left: 4px solid #f59e0b; }
.acad-article[data-accent="green"] { border-left: 4px solid var(--accent-green); }
.acad-article[data-accent="slate"] { border-left: 4px solid var(--text-faint); }

.acad-article > summary {
    display: flex;
    align-items: center;
    gap: 12px;
    padding: 20px 24px;
    cursor: pointer;
    list-style: none;
    user-select: none;
    transition: background-color 0.15s ease;
}

.acad-article > summary::-webkit-details-marker {
    display: none;
}

.acad-article > summary:hover {
    background: var(--bg-panel-hover);
}

.acad-article-icon {
    width: 40px;
    height: 40px;
    border-radius: var(--radius-sm);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 20px;
    flex-shrink: 0;
}

.acad-article[data-accent="purple"] .acad-article-icon {
    background: rgba(139, 92, 246, 0.1);
    color: var(--accent-purple);
}
.acad-article[data-accent="red"] .acad-article-icon {
    background: rgba(34, 211, 238, 0.1);
    color: var(--accent-red);
}
.acad-article[data-accent="blue"] .acad-article-icon {
    background: rgba(2, 132, 199, 0.1);
    color: var(--accent-blue);
}
.acad-article[data-accent="cyan"] .acad-article-icon {
    background: rgba(6, 182, 212, 0.1);
    color: var(--accent-cyan);
}
.acad-article[data-accent="amber"] .acad-article-icon {
    background: rgba(245, 158, 11, 0.1);
    color: #f59e0b;
}
.acad-article[data-accent="green"] .acad-article-icon {
    background: rgba(34, 197, 94, 0.1);
    color: var(--accent-green);
}
.acad-article[data-accent="slate"] .acad-article-icon {
    background: rgba(100, 116, 139, 0.1);
    color: var(--text-muted);
}

[data-theme="dark"] .acad-article[data-accent="purple"] .acad-article-icon { background: rgba(139, 92, 246, 0.15); }
[data-theme="dark"] .acad-article[data-accent="red"] .acad-article-icon { background: rgba(255, 59, 48, 0.15); }
[data-theme="dark"] .acad-article[data-accent="blue"] .acad-article-icon { background: rgba(2, 132, 199, 0.15); }
[data-theme="dark"] .acad-article[data-accent="cyan"] .acad-article-icon { background: rgba(6, 182, 212, 0.15); }
[data-theme="dark"] .acad-article[data-accent="amber"] .acad-article-icon { background: rgba(245, 158, 11, 0.15); }
[data-theme="dark"] .acad-article[data-accent="green"] .acad-article-icon { background: rgba(34, 197, 94, 0.15); }
[data-theme="dark"] .acad-article[data-accent="slate"] .acad-article-icon { background: rgba(100, 116, 139, 0.15); }

.acad-article-title {
    flex: 1;
    font-size: 17px;
    font-weight: 700;
    color: var(--text-main);
}

.acad-article-chevron {
    font-size: 20px;
    color: var(--text-faint);
    transition: transform 0.25s ease;
    flex-shrink: 0;
}

.acad-article[open] > summary .acad-article-chevron {
    transform: rotate(180deg);
}

.acad-article[open] > summary {
    border-bottom: 1px solid var(--border-color);
}

/* --- Article Body Content --- */
.acad-article-body {
    padding: 24px 28px 28px;
}

.acad-article-body p {
    font-size: 14px;
    line-height: 1.7;
    color: var(--text-muted);
    margin: 0 0 16px 0;
}

.acad-article-body p:last-child {
    margin-bottom: 0;
}

.acad-article-body h4 {
    font-size: 15px;
    font-weight: 700;
    color: var(--text-main);
    margin: 24px 0 10px 0;
}

.acad-article-body h4:first-child {
    margin-top: 0;
}

/* --- Tables --- */
.acad-table-wrap {
    overflow-x: auto;
    margin: 16px 0;
    border-radius: var(--radius-sm);
    border: 1px solid var(--border-color);
}

.acad-table {
    width: 100%;
    border-collapse: collapse;
    font-size: 13px;
}

.acad-table th {
    background: var(--bg-panel-hover);
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 0.5px;
    font-size: 11px;
    color: var(--text-faint);
    padding: 10px 14px;
    text-align: left;
    white-space: nowrap;
}

.acad-table td {
    padding: 10px 14px;
    color: var(--text-muted);
    border-top: 1px solid var(--border-color);
    vertical-align: top;
}

.acad-table tbody tr:hover {
    background: var(--bg-panel-hover);
}

.acad-table .acad-highlight {
    background: rgba(139, 92, 246, 0.06);
    font-weight: 600;
}

[data-theme="dark"] .acad-table .acad-highlight {
    background: rgba(139, 92, 246, 0.1);
}

/* --- Callout Boxes --- */
.acad-callout {
    display: flex;
    gap: 12px;
    padding: 14px 18px;
    border-radius: var(--radius-sm);
    margin: 16px 0;
    font-size: 13px;
    line-height: 1.6;
}

.acad-callout i {
    font-size: 20px;
    flex-shrink: 0;
    margin-top: 1px;
}

.acad-callout p {
    margin: 0 !important;
    font-size: 13px !important;
}

.acad-callout-tip {
    background: rgba(34, 197, 94, 0.08);
    border-left: 3px solid var(--accent-green);
    color: var(--text-muted);
}

.acad-callout-tip i {
    color: var(--accent-green);
}

.acad-callout-warn {
    background: rgba(245, 158, 11, 0.08);
    border-left: 3px solid #f59e0b;
    color: var(--text-muted);
}

.acad-callout-warn i {
    color: #f59e0b;
}

.acad-callout-info {
    background: rgba(2, 132, 199, 0.08);
    border-left: 3px solid var(--accent-blue);
    color: var(--text-muted);
}

.acad-callout-info i {
    color: var(--accent-blue);
}

[data-theme="dark"] .acad-callout-tip { background: rgba(34, 197, 94, 0.1); }
[data-theme="dark"] .acad-callout-warn { background: rgba(245, 158, 11, 0.1); }
[data-theme="dark"] .acad-callout-info { background: rgba(2, 132, 199, 0.1); }

/* --- Code Blocks (for naming patterns) --- */
.acad-code {
    display: inline;
    background: var(--bg-panel-hover);
    padding: 2px 7px;
    border-radius: 4px;
    font-family: 'Courier New', monospace;
    font-size: 12px;
    font-weight: 600;
    color: var(--accent-purple);
    border: 1px solid var(--border-color);
}

.acad-code-block {
    display: block;
    background: var(--bg-panel-hover);
    padding: 14px 18px;
    border-radius: var(--radius-sm);
    font-family: 'Courier New', monospace;
    font-size: 13px;
    color: var(--text-main);
    margin: 16px 0;
    border: 1px solid var(--border-color);
    overflow-x: auto;
    white-space: pre;
    line-height: 1.8;
}

/* --- Ordered/Unordered Lists --- */
.acad-article-body ol,
.acad-article-body ul {
    margin: 12px 0 16px 0;
    padding-left: 24px;
    font-size: 14px;
    line-height: 1.7;
    color: var(--text-muted);
}

.acad-article-body li {
    margin-bottom: 6px;
}

.acad-article-body li strong {
    color: var(--text-main);
}

/* --- Back to Top Button --- */
.acad-back-to-top {
    position: fixed;
    bottom: 32px;
    right: 32px;
    width: 44px;
    height: 44px;
    border-radius: 50%;
    background: var(--accent-purple);
    color: white;
    border: none;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 22px;
    box-shadow: 0 4px 12px rgba(139, 92, 246, 0.35);
    opacity: 0;
    visibility: hidden;
    transform: translateY(8px);
    transition: opacity 0.25s ease, visibility 0.25s ease, transform 0.25s ease, background-color 0.2s ease;
    z-index: 100;
}

.acad-back-to-top.acad-visible {
    opacity: 1;
    visibility: visible;
    transform: translateY(0);
}

.acad-back-to-top:hover {
    background: var(--accent-blue);
    box-shadow: 0 6px 16px rgba(2, 132, 199, 0.4);
}

/* --- Responsive --- */
@media (max-width: 768px) {
    .acad-hero {
        flex-direction: column;
        padding: 28px 24px;
        text-align: center;
    }

    .acad-hero-title {
        font-size: 26px;
    }

    .acad-hero-graphic {
        display: none;
    }

    .acad-topics-grid {
        grid-template-columns: 1fr;
    }

    .acad-article > summary {
        padding: 16px 18px;
    }

    .acad-article-body {
        padding: 18px 20px 22px;
    }

    .acad-back-to-top {
        bottom: 20px;
        right: 20px;
        width: 40px;
        height: 40px;
        font-size: 20px;
    }
}

@media (max-width: 480px) {
    .acad-hero {
        padding: 24px 18px;
    }

    .acad-hero-title {
        font-size: 22px;
    }

    .acad-article-title {
        font-size: 15px;
    }
}