/* ==========================================================================
   SERIES TAXONOMY - MODERN CURRICULUM ROADMAP (v2.5.4)
   Theme: theme_vnhte_com
   ========================================================================== */

.series-page-main {
    min-height: 100vh;
    padding-top: calc(var(--header-height) + var(--space-lg));
    padding-bottom: var(--space-hero);
    background: var(--surface-canvas, var(--surface));
    overflow-x: clip;
    width: 100%;
}

.series-page-main .container-main,
.series-page-main > .container-main {
    max-width: var(--container-max);
    margin: 0 auto;
    padding: 0 var(--space-xl);
    width: 100%;
    box-sizing: border-box;
}

/* ==========================================================================
   1. HERO SHOWCASE BANNER
   ========================================================================== */
.series-hero-banner {
    position: relative;
    background: radial-gradient(ellipse at 85% 15%, rgba(20, 86, 240, 0.05), transparent 50%),
                radial-gradient(ellipse at 15% 85%, rgba(255, 85, 48, 0.04), transparent 50%),
                var(--canvas);
    border: 1px solid var(--hairline);
    border-radius: var(--radius-xxl);
    padding: 38px 44px;
    margin: 16px 0 36px;
    overflow: hidden;
    box-shadow: var(--shadow-level-1);
    width: 100%;
    box-sizing: border-box;
}

/* Background Ambient Watermark */
.series-watermark-icon {
    position: absolute;
    right: 0;
    bottom: 0;
    width: 240px;
    height: 240px;
    opacity: 0.04;
    color: var(--ink);
    pointer-events: none;
    z-index: 0;
    overflow: hidden;
}

.series-hero-content {
    position: relative;
    z-index: 1;
}

/* Top Badge Strip */
.series-hero-tags {
    display: flex;
    flex-wrap: wrap;
    align-items: center;
    gap: 10px;
    margin-bottom: 16px;
}

.series-pill-badge {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    padding: 4px 12px;
    border-radius: var(--radius-full);
    font-size: var(--text-micro);
    font-weight: var(--weight-bold);
    text-transform: uppercase;
    letter-spacing: 0.6px;
}

.series-pill-coral {
    background: rgba(255, 85, 48, 0.1);
    color: var(--brand-coral);
    border: 1px solid rgba(255, 85, 48, 0.25);
}

.series-pill-blue {
    background: rgba(20, 86, 240, 0.08);
    color: var(--brand-blue);
    border: 1px solid rgba(20, 86, 240, 0.2);
}

.series-update-meta {
    display: inline-flex;
    align-items: center;
    gap: 5px;
    font-size: var(--text-caption);
    color: var(--stone);
    margin-left: auto;
}

/* Title & Description */
.series-hero-title {
    font-family: var(--font-heading);
    font-size: clamp(26px, 3.5vw, 42px);
    font-weight: 800;
    color: var(--ink);
    line-height: 1.22;
    margin-bottom: 14px;
    letter-spacing: -0.02em;
}

.series-hero-desc {
    color: var(--slate);
    font-size: var(--text-base);
    line-height: 1.65;
    max-width: 820px;
    margin-bottom: 24px;
}

/* 4 Metric Cards Grid */
.series-metric-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 16px;
    margin-bottom: 28px;
}

.series-metric-card {
    background: var(--surface);
    border: 1px solid var(--hairline);
    border-radius: var(--radius-xl);
    padding: 16px 18px;
    display: flex;
    align-items: center;
    gap: 14px;
    transition: transform 0.25s var(--ease-spring), border-color 0.25s ease, box-shadow 0.25s var(--ease-spring);
}

.series-metric-card:hover {
    transform: translateY(-2px);
    border-color: rgba(20, 86, 240, 0.25);
    box-shadow: var(--shadow-level-1);
}

.metric-icon-wrap {
    width: 38px;
    height: 38px;
    border-radius: var(--radius-sm);
    display: flex;
    align-items: center;
    justify-content: center;
    flex-shrink: 0;
}

.metric-coral {
    background: rgba(255, 85, 48, 0.12);
    color: var(--brand-coral);
}

.metric-blue {
    background: rgba(20, 86, 240, 0.12);
    color: var(--brand-blue);
}

.metric-purple {
    background: rgba(139, 92, 246, 0.12);
    color: #8b5cf6;
}

.metric-green {
    background: rgba(16, 185, 129, 0.12);
    color: #059669;
}

.metric-info {
    display: flex;
    flex-direction: column;
}

.metric-label {
    font-size: 10px;
    text-transform: uppercase;
    letter-spacing: 0.5px;
    color: var(--stone);
    font-weight: var(--weight-bold);
    margin-bottom: 2px;
}

.metric-value {
    font-family: var(--font-mono);
    font-size: 14px;
    font-weight: 700;
    color: var(--ink);
    line-height: 1.2;
}

/* Action & Author Row */
.series-hero-footer {
    display: flex;
    align-items: center;
    justify-content: space-between;
    flex-wrap: wrap;
    gap: 16px;
    padding-top: 20px;
    border-top: 1px solid var(--hairline-soft);
}

.series-cta-group {
    display: flex;
    align-items: center;
    gap: 12px;
    flex-wrap: wrap;
}

.btn-series-primary {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    background: var(--primary);
    color: var(--on-primary, #ffffff) !important;
    padding: 11px 22px;
    border-radius: var(--radius-full);
    font-size: var(--text-sm);
    font-weight: var(--weight-bold);
    text-decoration: none;
    border: 1px solid var(--primary);
    box-shadow: var(--shadow-sm);
    transition: all var(--transition-fast);
}

.btn-series-primary:hover {
    transform: translateY(-1px);
    box-shadow: var(--shadow-level-2);
    background: #000000;
}

.btn-series-secondary {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    background: var(--surface);
    color: var(--ink);
    padding: 11px 20px;
    border-radius: var(--radius-full);
    font-size: var(--text-sm);
    font-weight: var(--weight-semibold);
    text-decoration: none;
    border: 1px solid var(--hairline);
    transition: all var(--transition-fast);
}

.btn-series-secondary:hover {
    background: var(--canvas);
    border-color: var(--charcoal);
    transform: translateY(-1px);
}

.series-instructor-pill {
    display: flex;
    align-items: center;
    gap: 10px;
    background: var(--surface);
    border: 1px solid var(--hairline);
    padding: 6px 16px 6px 8px;
    border-radius: var(--radius-full);
}

.instructor-avatar {
    width: 32px;
    height: 32px;
    border-radius: 50%;
    object-fit: cover;
    border: 1.5px solid var(--hairline);
}

.instructor-text {
    display: flex;
    flex-direction: column;
}

.instructor-sub {
    font-size: 10px;
    color: var(--stone);
    line-height: 1;
    margin-bottom: 2px;
}

.instructor-name {
    font-size: 12px;
    font-weight: var(--weight-bold);
    color: var(--ink);
    line-height: 1.2;
}

/* ==========================================================================
   2. MAIN CONTENT LAYOUT (8 / 4)
   ========================================================================== */
.series-layout-grid {
    display: grid;
    grid-template-columns: minmax(0, 1fr) 340px;
    gap: 32px;
    align-items: flex-start;
    width: 100%;
    box-sizing: border-box;
}

/* Curriculum Section Header */
.curriculum-main-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    margin-bottom: 24px;
    padding-bottom: 14px;
    border-bottom: 1px solid var(--hairline);
}

.curriculum-title-wrap h2 {
    font-family: var(--font-heading);
    font-size: 22px;
    font-weight: var(--weight-bold);
    color: var(--ink);
    margin: 0 0 4px 0;
    display: flex;
    align-items: center;
    gap: 10px;
}

.curriculum-title-wrap h2 svg {
    color: var(--brand-coral);
}

.curriculum-sub {
    font-size: var(--text-sm);
    color: var(--slate);
    margin: 0;
}

.curriculum-count-badge {
    font-family: var(--font-mono);
    font-size: var(--text-caption);
    font-weight: var(--weight-bold);
    color: var(--slate);
    background: var(--surface);
    border: 1px solid var(--hairline);
    padding: 4px 12px;
    border-radius: var(--radius-full);
}

/* Chapter / Milestone Header */
.chapter-block-header {
    margin: 28px 0 14px;
    padding-top: 20px;
    border-top: 1px dashed var(--hairline);
}

.chapter-block-header:first-child {
    margin-top: 0;
    padding-top: 0;
    border-top: none;
}

.chapter-badge-title {
    display: flex;
    align-items: center;
    gap: 10px;
    margin-bottom: 4px;
}

.chapter-index-num {
    width: 24px;
    height: 24px;
    background: var(--canvas);
    border: 1px solid var(--hairline);
    color: var(--brand-coral);
    border-radius: 6px;
    font-family: var(--font-mono);
    font-size: 11px;
    font-weight: 700;
    display: flex;
    align-items: center;
    justify-content: center;
}

.chapter-title {
    font-family: var(--font-heading);
    font-size: 17px;
    font-weight: var(--weight-bold);
    color: var(--ink);
    margin: 0;
}

.chapter-desc {
    font-size: 12px;
    color: var(--slate);
    margin: 0 0 0 34px;
    line-height: 1.5;
}

/* ==========================================================================
   3. CURRICULUM ITEM CARD (RESTRUCTURED)
   ========================================================================== */
.curriculum-item {
    display: flex;
    align-items: center;
    gap: 20px;
    padding: 18px 24px;
    background: var(--canvas);
    border: 1px solid var(--hairline);
    border-radius: var(--radius-xl);
    margin-bottom: 14px;
    transition: transform 0.28s var(--ease-spring), border-color 0.25s ease, box-shadow 0.28s var(--ease-spring), background 0.25s ease;
    position: relative;
    box-shadow: var(--shadow-level-1);
}

.curriculum-item:hover {
    transform: translateY(-2px);
    border-color: var(--charcoal);
    box-shadow: var(--shadow-level-2);
}

/* Completed card state */
.curriculum-item.is-completed {
    border-color: rgba(16, 185, 129, 0.45);
    background: rgba(16, 185, 129, 0.025);
}

/* Thumbnail Wrap with integrated Step Badge */
.curriculum-thumb-wrap {
    width: 136px;
    height: 84px;
    border-radius: var(--radius-md);
    overflow: hidden;
    flex-shrink: 0;
    position: relative;
    border: 1px solid var(--hairline-soft);
    background: var(--surface-soft);
}

.curriculum-thumb-img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    display: block;
    transition: transform 0.4s cubic-bezier(0.16, 1, 0.3, 1);
}

.curriculum-item:hover .curriculum-thumb-img {
    transform: scale(1.06);
}

.curriculum-thumb-fallback {
    width: 100%;
    height: 100%;
    display: flex;
    align-items: center;
    justify-content: center;
    background: var(--surface);
    color: var(--brand-coral);
}

/* Integrated Step Number on Thumbnail */
.thumb-step-badge {
    position: absolute;
    top: 6px;
    left: 6px;
    background: rgba(10, 10, 10, 0.8);
    backdrop-filter: blur(4px);
    color: #ffffff;
    font-family: var(--font-mono);
    font-size: 11px;
    font-weight: 700;
    padding: 2px 7px;
    border-radius: 6px;
    line-height: 1.2;
    z-index: 2;
    letter-spacing: 0.5px;
    transition: all var(--transition-fast);
}

.curriculum-item.is-completed .thumb-step-badge {
    background: #059669;
}

/* Content Details */
.curriculum-content-col {
    flex: 1;
    min-width: 0;
}

.curriculum-meta-row {
    display: flex;
    flex-wrap: wrap;
    align-items: center;
    gap: 8px;
    margin-bottom: 6px;
    font-size: 12px;
    color: var(--stone);
}

.curriculum-meta-row .badge {
    font-size: 11px;
    padding: 2px 8px;
}

.meta-dot {
    color: var(--hairline-soft);
}

.meta-stat {
    display: inline-flex;
    align-items: center;
    gap: 4px;
    color: var(--slate);
    font-size: 12px;
}

.curriculum-post-title {
    font-family: var(--font-sans);
    font-size: 16.5px;
    font-weight: 700;
    line-height: 1.38;
    margin: 0 0 4px 0;
}

.curriculum-post-title a {
    color: var(--ink);
    text-decoration: none;
    display: -webkit-box;
    -webkit-line-clamp: 2;
    line-clamp: 2;
    -webkit-box-orient: vertical;
    overflow: hidden;
    transition: color var(--transition-fast);
}

.curriculum-post-title a:hover {
    color: var(--brand-coral);
}

.curriculum-post-excerpt {
    font-family: var(--font-sans);
    font-size: 13px;
    color: var(--slate);
    line-height: 1.5;
    margin: 0;
    display: -webkit-box;
    -webkit-line-clamp: 2;
    line-clamp: 2;
    -webkit-box-orient: vertical;
    overflow: hidden;
}

/* Actions Column */
.curriculum-actions-col {
    display: flex;
    align-items: center;
    gap: 10px;
    flex-shrink: 0;
}

.btn-toggle-learned {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    padding: 8px 14px;
    border-radius: var(--radius-full);
    border: 1px solid var(--hairline);
    background: var(--surface);
    color: var(--slate);
    font-size: 12px;
    font-weight: 600;
    cursor: pointer;
    transition: all var(--transition-fast);
    line-height: 1;
}

.btn-toggle-learned:hover {
    border-color: #059669;
    color: #059669;
    background: rgba(16, 185, 129, 0.06);
    transform: translateY(-1px);
}

.btn-toggle-learned.is-checked {
    background: rgba(16, 185, 129, 0.12);
    border-color: #059669;
    color: #059669;
}

.btn-learn-cta {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    padding: 8px 20px;
    border-radius: var(--radius-full);
    font-size: 13px;
    font-weight: 600;
    text-decoration: none;
    background: var(--surface);
    color: var(--ink);
    border: 1px solid var(--hairline);
    transition: all 0.25s var(--ease-spring);
    white-space: nowrap;
    line-height: 1;
}

.btn-learn-cta svg {
    transition: transform 0.2s var(--ease-spring);
}

.btn-learn-cta:hover {
    background: var(--primary);
    color: var(--on-primary);
    border-color: var(--primary);
    transform: translateY(-1px);
    box-shadow: var(--shadow-level-2);
}

.btn-learn-cta:hover svg {
    transform: translateX(3px);
}

/* ==========================================================================
   4. SMART SIDEBAR (STICKY PROGRESS)
   ========================================================================== */
.series-sidebar-col {
    display: flex;
    flex-direction: column;
    gap: 20px;
}

/* Dedicated Sticky Container for Progress */
.sidebar-sticky-progress {
    position: sticky;
    top: calc(var(--header-height) + 16px);
    z-index: 10;
}

.series-progress-widget {
    background: var(--canvas);
    border: 1px solid var(--hairline);
    border-radius: var(--radius-lg);
    padding: 20px;
    box-shadow: var(--shadow-sm);
}

.progress-card-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    margin-bottom: 14px;
}

.progress-card-title {
    font-weight: 700;
    font-size: 14px;
    color: var(--ink);
    display: flex;
    align-items: center;
    gap: 6px;
}

.progress-card-title svg {
    color: var(--brand-coral);
}

.progress-stat-pill {
    font-family: var(--font-mono);
    font-size: 11px;
    font-weight: 700;
    padding: 3px 8px;
    border-radius: var(--radius-full);
    background: rgba(255, 85, 48, 0.1);
    color: var(--brand-coral);
    border: 1px solid rgba(255, 85, 48, 0.25);
}

.progress-track-wrap {
    margin-bottom: 14px;
}

.progress-status-row {
    display: flex;
    justify-content: space-between;
    font-size: 12px;
    font-weight: 600;
    color: var(--slate);
    margin-bottom: 8px;
}

.progress-bar-rail {
    width: 100%;
    height: 8px;
    background: var(--surface-soft);
    border: 1px solid var(--hairline);
    border-radius: 9999px;
    overflow: hidden;
}

.progress-bar-fill {
    height: 100%;
    background: linear-gradient(90deg, var(--brand-coral), #ff7a59);
    border-radius: 9999px;
    transition: width 0.35s ease, background 0.35s ease;
}

.progress-bar-fill.is-completed {
    background: linear-gradient(90deg, #10b981, #059669);
}

.btn-sidebar-resume {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    width: 100%;
    padding: 10px 16px;
    border-radius: var(--radius-full);
    font-size: 12px;
    font-weight: 700;
    background: var(--primary);
    color: #ffffff;
    text-decoration: none;
    border: 1px solid var(--primary);
    box-shadow: var(--shadow-sm);
    transition: all var(--transition-fast);
}

.btn-sidebar-resume:hover {
    background: #000000;
    transform: translateY(-1px);
}

.progress-help-text {
    font-size: 11px;
    color: var(--stone);
    text-align: center;
    margin: 8px 0 0 0;
}

/* Normal Non-Sticky Sidebar Widgets */
.series-sidebar-card {
    background: var(--canvas);
    border: 1px solid var(--hairline);
    border-radius: var(--radius-lg);
    padding: 20px;
}

.sidebar-card-header {
    display: flex;
    align-items: center;
    gap: 8px;
    margin-bottom: 14px;
    padding-bottom: 10px;
    border-bottom: 1px solid var(--hairline);
    font-size: 14px;
    font-weight: 700;
    color: var(--ink);
}

.sidebar-card-header svg {
    color: var(--brand-coral);
}

/* Instructor Box */
.instructor-card-profile {
    display: flex;
    align-items: center;
    gap: 12px;
    margin-bottom: 10px;
}

.instructor-big-avatar {
    width: 46px;
    height: 46px;
    border-radius: 50%;
    object-fit: cover;
    border: 2px solid var(--hairline);
}

.instructor-profile-text h4 {
    margin: 0 0 2px 0;
    font-size: 14px;
    font-weight: 700;
    color: var(--ink);
}

.instructor-profile-text span {
    font-size: 11px;
    color: var(--brand-blue);
    font-weight: 600;
}

.instructor-bio {
    font-size: 12px;
    color: var(--slate);
    line-height: 1.55;
    margin-bottom: 14px;
}

.instructor-social-links {
    display: flex;
    align-items: center;
    gap: 8px;
}

.btn-social-chip {
    flex: 1;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 6px;
    padding: 6px 12px;
    border-radius: var(--radius-md);
    background: var(--surface);
    border: 1px solid var(--hairline);
    color: var(--ink);
    font-size: 12px;
    font-weight: 600;
    text-decoration: none;
    transition: all var(--transition-fast);
}

.btn-social-chip:hover {
    background: var(--surface-soft);
    border-color: var(--charcoal);
}

/* Key Learnings */
.learnings-list {
    list-style: none;
    padding: 0;
    margin: 0;
    display: flex;
    flex-direction: column;
    gap: 8px;
}

.learnings-list li {
    display: flex;
    align-items: flex-start;
    gap: 8px;
    font-size: 12px;
    color: var(--slate);
    line-height: 1.45;
}

.learning-check-icon {
    width: 16px;
    height: 16px;
    border-radius: 50%;
    background: rgba(16, 185, 129, 0.12);
    color: #059669;
    font-size: 9px;
    font-weight: 700;
    display: flex;
    align-items: center;
    justify-content: center;
    flex-shrink: 0;
    margin-top: 2px;
}

/* Tech Stack Badges */
.tech-badges-wrap {
    display: flex;
    flex-wrap: wrap;
    gap: 8px;
}

.tech-pill {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    padding: 4px 10px;
    border-radius: var(--radius-sm);
    font-family: var(--font-mono);
    font-size: 11px;
    font-weight: 600;
    background: var(--surface);
    border: 1px solid var(--hairline);
    color: var(--ink);
}

/* Share Block */
.share-action-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 8px;
    margin-bottom: 8px;
}

.btn-share-social {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 6px;
    padding: 7px 10px;
    border-radius: var(--radius-md);
    background: var(--surface);
    border: 1px solid var(--hairline);
    color: var(--ink);
    font-size: 12px;
    font-weight: 600;
    text-decoration: none;
    transition: all var(--transition-fast);
}

.btn-share-social:hover {
    border-color: var(--charcoal);
}

.btn-copy-series-url {
    width: 100%;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 6px;
    padding: 8px 12px;
    border-radius: var(--radius-md);
    background: var(--surface);
    border: 1px solid var(--hairline);
    color: var(--ink);
    font-size: 12px;
    font-weight: 600;
    cursor: pointer;
    transition: all var(--transition-fast);
}

.btn-copy-series-url:hover {
    border-color: var(--charcoal);
}

.copy-toast-alert {
    margin-top: 8px;
    padding: 6px 10px;
    border-radius: var(--radius-sm);
    background: rgba(16, 185, 129, 0.12);
    border: 1px solid rgba(16, 185, 129, 0.25);
    color: #059669;
    font-size: 11px;
    font-weight: 600;
    text-align: center;
    display: none;
}

/* ==========================================================================
   5. RESPONSIVE DESIGN
   ========================================================================== */
@media (max-width: 1024px) {
    .series-layout-grid {
        grid-template-columns: minmax(0, 1fr);
        gap: 28px;
    }

    .sidebar-sticky-progress {
        position: static;
    }
}

@media (max-width: 768px) {
    .series-page-main {
        padding-top: calc(var(--header-height) + var(--space-md));
    }

    .series-page-main .container-main,
    .series-page-main > .container-main {
        padding: 0 var(--space-md);
    }

    .series-hero-banner {
        padding: 24px 16px;
        border-radius: var(--radius-lg);
        margin: 12px 0 24px;
    }

    .series-metric-grid {
        grid-template-columns: repeat(2, 1fr);
        gap: 10px;
    }

    .series-hero-footer {
        flex-direction: column;
        align-items: stretch;
        gap: 14px;
    }

    .series-cta-group {
        width: 100%;
        flex-direction: column;
    }

    .btn-series-primary,
    .btn-series-secondary {
        width: 100%;
        justify-content: center;
        text-align: center;
        box-sizing: border-box;
    }

    .series-instructor-pill {
        width: 100%;
        box-sizing: border-box;
    }
}

/* Mobile: Curriculum Item Card Fix */
@media (max-width: 640px) {
    .curriculum-item {
        flex-direction: column;
        align-items: stretch;
        gap: 12px;
        padding: 14px;
        width: 100%;
        box-sizing: border-box;
    }

    /* Top row: Number + Thumbnail + Level Pill */
    .curriculum-mobile-top-row {
        display: flex;
        align-items: center;
        gap: 12px;
        width: 100%;
    }

    .step-number-badge {
        width: 32px;
        height: 32px;
        font-size: 12px;
        flex-shrink: 0;
    }

    .curriculum-thumb-wrap {
        width: 88px;
        height: 54px;
        flex-shrink: 0;
    }

    .curriculum-mobile-meta-tags {
        display: flex;
        flex-direction: column;
        gap: 4px;
        min-width: 0;
        flex: 1;
    }

    .curriculum-meta-row {
        display: none !important;
    }

    .learned-label {
        display: inline !important;
    }

    /* Content */
    .curriculum-content-col {
        width: 100%;
    }

    .curriculum-post-title {
        font-size: 14px;
        margin-bottom: 4px;
    }

    .curriculum-post-excerpt {
        font-size: 11px;
    }

    /* Bottom row: Checkbox + Action button across full width */
    .curriculum-actions-col {
        display: flex;
        align-items: center;
        justify-content: space-between;
        width: 100%;
        padding-top: 10px;
        border-top: 1px solid var(--hairline-soft);
        box-sizing: border-box;
    }

    .btn-toggle-learned {
        width: auto;
        padding: 6px 12px;
        gap: 6px;
        font-size: 11px;
        font-weight: 600;
        flex-shrink: 0;
    }

    .btn-learn-cta {
        flex: 1;
        justify-content: center;
        margin-left: 8px;
        box-sizing: border-box;
    }
}

@media (max-width: 440px) {
    .series-metric-grid {
        grid-template-columns: 1fr;
    }
}

/* ==========================================================================
   CPT SERIES MODERN ROADMAP & SYLLABUS UPGRADES (v2.6)
   ========================================================================== */

/* 1. Bento Hero Enhancements */
.series-cta-btn {
    background: var(--brand-coral, #ff5530);
    color: #ffffff !important;
    text-decoration: none;
    box-shadow: 0 4px 14px rgba(255, 85, 48, 0.28);
    transition: all 0.25s cubic-bezier(0.16, 1, 0.3, 1);
}

.series-cta-btn:hover {
    background: #e0441e;
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(255, 85, 48, 0.38);
    color: #ffffff !important;
}

.series-cover-wrapper {
    position: relative;
    border-radius: var(--radius-xl, 20px);
    overflow: hidden;
    border: 1px solid var(--hairline);
    background: var(--surface);
    box-shadow: var(--shadow-sm);
}

.series-cover-wrapper img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    display: block;
    transition: transform 0.4s ease;
}

.series-cover-wrapper:hover img {
    transform: scale(1.03);
}

/* 2. Personal Learning Tracker */
.personal-tracker-card {
    background: rgba(20, 86, 240, 0.04);
    border: 1px solid rgba(20, 86, 240, 0.16);
    border-radius: var(--radius-xl, 20px);
    transition: border-color var(--transition-fast), box-shadow var(--transition-fast);
}

.personal-tracker-card:hover {
    border-color: rgba(20, 86, 240, 0.3);
    box-shadow: 0 4px 20px -2px rgba(20, 86, 240, 0.08);
}

#personalProgressBar {
    transition: width 0.5s cubic-bezier(0.16, 1, 0.3, 1);
}

/* 3. Chapter Milestones & Curriculum */
.chapter-milestone-header {
    position: relative;
    padding-left: 2px;
}

.chapter-milestone-header h3 {
    letter-spacing: -0.01em;
}

/* 4. Interactive Timeline Lesson Cards */
.timeline-lesson-card {
    transition: transform 0.22s cubic-bezier(0.16, 1, 0.3, 1),
                border-color 0.22s ease,
                box-shadow 0.22s ease,
                background-color 0.22s ease;
    border: 1px solid var(--hairline);
    background: var(--surface);
    border-radius: var(--radius-xl, 20px);
}

.timeline-lesson-card:hover {
    transform: translateY(-2px);
    border-color: var(--brand-blue);
    box-shadow: var(--shadow-md, 0 10px 25px -5px rgba(0, 0, 0, 0.06));
}

.timeline-lesson-card .lesson-step-badge {
    transition: all 0.22s ease;
    border-radius: var(--radius-lg, 12px);
}

.timeline-lesson-card:hover .lesson-step-badge {
    background: var(--brand-blue);
    border-color: var(--brand-blue);
    color: #ffffff;
}

.timeline-lesson-card.is-completed {
    border-color: rgba(16, 185, 129, 0.35);
    background: rgba(16, 185, 129, 0.025);
}

.timeline-lesson-card.is-completed .lesson-step-badge {
    background: #10b981;
    border-color: #10b981;
    color: #ffffff;
}

.timeline-lesson-card.is-completed .lesson-title a {
    color: var(--slate);
}

.timeline-lesson-card.is-completed .lesson-status-badge {
    background: rgba(16, 185, 129, 0.12);
    color: #059669;
    border: 1px solid rgba(16, 185, 129, 0.25);
}

/* Lesson Complete Toggle Button */
.lesson-complete-toggle {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 36px;
    height: 36px;
    border: 1px solid var(--hairline);
    border-radius: var(--radius-md, 10px);
    background: var(--canvas);
    color: var(--stone);
    cursor: pointer;
    transition: all 0.2s cubic-bezier(0.16, 1, 0.3, 1);
}

.lesson-complete-toggle:hover {
    border-color: #10b981;
    color: #10b981;
    background: rgba(16, 185, 129, 0.08);
    transform: scale(1.05);
}

.lesson-complete-toggle.is-active {
    background: #10b981;
    border-color: #10b981;
    color: #ffffff;
    box-shadow: 0 2px 8px rgba(16, 185, 129, 0.35);
}

/* ==========================================================================
   5. ARCHIVE CATALOG & EDITORIAL SHOWCASE CARDS (DESIGN.md Reference)
   ========================================================================== */

/* Catalog Hero Additions */
.series-catalog-hero {
    background: radial-gradient(ellipse at 85% 15%, rgba(20, 86, 240, 0.05), transparent 50%),
                radial-gradient(ellipse at 15% 85%, rgba(255, 85, 48, 0.04), transparent 50%),
                var(--canvas);
}

.series-search-bar-wrap {
    position: relative;
    max-width: 580px;
}

.series-search-input {
    font-family: var(--font-sans);
    transition: all var(--transition-fast);
    box-shadow: inset 0 1px 2px rgba(0, 0, 0, 0.03);
}

.series-search-input:focus {
    box-shadow: 0 0 0 3px rgba(20, 86, 240, 0.12);
}

/* Filter Navigation Tabs */
.series-filter-nav {
    display: flex;
    flex-wrap: wrap;
    align-items: center;
    gap: 10px;
}

.series-filter-pill {
    font-family: var(--font-sans);
    font-size: var(--text-sm);
    font-weight: var(--weight-semibold);
    padding: 8px 20px;
    border-radius: var(--radius-full);
    border: 1px solid var(--hairline);
    background: var(--canvas);
    color: var(--charcoal);
    cursor: pointer;
    transition: all var(--transition-base);
    box-sizing: border-box;
    display: inline-flex;
    align-items: center;
    gap: 6px;
    line-height: 1.2;
}

.series-filter-pill:hover {
    border-color: var(--charcoal);
    background: var(--surface);
    color: var(--ink);
    transform: translateY(-1px);
}

.series-filter-pill.is-active {
    background: var(--primary) !important;
    border-color: var(--primary) !important;
    color: var(--on-primary) !important;
    box-shadow: var(--shadow-level-2);
}

.series-filter-pill .filter-count-badge {
    opacity: 0.65;
    font-size: 11px;
}

.series-filter-pill.is-active .filter-count-badge {
    opacity: 0.85;
}

/* Editorial Series Card (DESIGN.md Section 5.3 & Bento Principles) */
.showcase-series-card {
    background: var(--canvas);
    border: 1px solid var(--hairline);
    border-radius: var(--radius-xl);
    padding: 20px;
    box-shadow: var(--shadow-level-1);
    display: flex;
    flex-direction: column;
    transition: transform var(--transition-base), border-color var(--transition-base), box-shadow var(--transition-base);
    position: relative;
}

.showcase-series-card:hover {
    transform: translateY(-3px);
    border-color: var(--charcoal);
    box-shadow: var(--shadow-level-3);
}

/* Cover Image Container */
.showcase-thumb-box {
    border-radius: var(--radius-lg);
    background: var(--surface-soft);
}

.showcase-thumb-box img {
    will-change: transform;
}

/* Card Header & Titles */
.showcase-card-title {
    font-family: var(--font-sans);
    font-size: 18px;
    font-weight: 700;
    color: var(--ink);
    line-height: 1.35;
    margin: 0 0 6px 0;
}

.showcase-card-title a {
    color: var(--ink);
    text-decoration: none;
    transition: color var(--transition-fast);
    display: -webkit-box;
    -webkit-line-clamp: 2;
    line-clamp: 2;
    -webkit-box-orient: vertical;
    overflow: hidden;
}

.showcase-card-title a:hover {
    color: var(--brand-coral);
}

.showcase-card-desc {
    font-family: var(--font-sans);
    font-size: 13.5px;
    color: var(--slate);
    line-height: 1.55;
    margin: 0;
    display: -webkit-box;
    -webkit-line-clamp: 2;
    line-clamp: 2;
    -webkit-box-orient: vertical;
    overflow: hidden;
}

/* Personalized Learning Progress Bar on Card */
.series-card-progress-box {
    transition: all var(--transition-fast);
}

.showcase-series-card:hover .series-card-progress-box {
    background: var(--canvas);
    border-color: var(--hairline);
}

.card-progress-bar {
    transition: width 0.6s cubic-bezier(0.16, 1, 0.3, 1);
}

/* Syllabus Mini Preview with Vertical Roadmap Timeline */
.catalog-lesson-preview {
    background: var(--surface);
    border: 1px solid var(--hairline-soft);
    border-radius: var(--radius-lg);
    padding: 14px 16px;
    transition: all var(--transition-fast);
    position: relative;
}

.catalog-lesson-preview .preview-heading {
    font-size: 11px;
    text-transform: uppercase;
    font-weight: 700;
    color: var(--stone);
    letter-spacing: 0.5px;
}

.showcase-card-list {
    position: relative;
    padding-left: 2px;
}

/* Timeline Vertical Line */
.showcase-card-list::before {
    content: '';
    position: absolute;
    top: 11px;
    bottom: 11px;
    left: 10px;
    width: 2px;
    background: linear-gradient(180deg, var(--hairline) 0%, rgba(20, 86, 240, 0.25) 100%);
    z-index: 1;
}

.showcase-card-list li {
    position: relative;
    z-index: 2;
    transition: transform 0.22s var(--ease-spring);
}

.showcase-card-list li:hover {
    transform: translateX(3px);
}

.showcase-card-list .sub-step {
    font-family: var(--font-mono);
    font-size: 10px;
    font-weight: 700;
    color: var(--slate);
    background: var(--canvas);
    border: 1.5px solid var(--hairline);
    width: 22px;
    height: 22px;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    border-radius: var(--radius-full);
    flex-shrink: 0;
    transition: all 0.22s var(--ease-spring);
    box-shadow: 0 1px 3px rgba(0, 0, 0, 0.04);
}

.showcase-card-list li:hover .sub-step {
    border-color: var(--brand-blue);
    background: var(--brand-blue);
    color: #ffffff;
    box-shadow: 0 0 8px rgba(20, 86, 240, 0.35);
    transform: scale(1.08);
}

.showcase-card-list li a {
    color: var(--charcoal);
    transition: color var(--transition-fast);
}

.showcase-card-list li:hover a {
    color: var(--brand-blue);
}

/* Tech Tags Pills */
.tech-tag-pill {
    font-family: var(--font-mono);
    font-size: 11px;
    font-weight: 600;
    padding: 3px 9px;
    border-radius: var(--radius-full);
    background: var(--surface);
    border: 1px solid var(--hairline);
    color: var(--slate);
    line-height: 1.2;
    letter-spacing: 0.2px;
    transition: all 0.2s var(--ease-spring);
}

.showcase-series-card:hover .tech-tag-pill {
    background: var(--canvas);
    border-color: var(--stone);
    color: var(--charcoal);
}

/* Card CTA Button */
.showcase-card-footer .btn-primary {
    border-radius: var(--radius-full);
    font-size: 13.5px;
    font-weight: 600;
    padding: 9px 18px;
    box-shadow: var(--shadow-sm);
    transition: all var(--transition-fast);
}

.showcase-card-footer .btn-primary:hover {
    transform: translateY(-1px);
    box-shadow: var(--shadow-level-2);
}

/* Small Pill Buttons */
.btn-sm-pill {
    padding: 6px 16px !important;
    font-size: var(--text-caption) !important;
    border-radius: var(--radius-full) !important;
}