/* ===== Calculator Library Page ===== */

/* Hero */
.lib-hero {
    background: var(--bg-hero);
    padding: var(--space-16) 0 var(--space-12);
    position: relative;
    overflow: hidden;
}
.lib-hero::before {
    content: '';
    position: absolute;
    inset: 0;
    background:
        radial-gradient(ellipse at 20% 60%, rgba(51, 129, 255, 0.18) 0%, transparent 55%),
        radial-gradient(ellipse at 80% 20%, rgba(249, 115, 22, 0.12) 0%, transparent 50%),
        radial-gradient(ellipse at 60% 90%, rgba(139, 92, 246, 0.1) 0%, transparent 50%);
}
.lib-hero::after {
    content: '';
    position: absolute;
    inset: 0;
    background-image:
        linear-gradient(rgba(255,255,255,0.03) 1px, transparent 1px),
        linear-gradient(90deg, rgba(255,255,255,0.03) 1px, transparent 1px);
    background-size: 60px 60px;
    animation: gridMove 20s linear infinite;
}
@keyframes gridMove {
    0% { transform: translate(0,0); }
    100% { transform: translate(60px,60px); }
}
.lib-hero-inner {
    position: relative;
    z-index: 2;
    text-align: center;
    max-width: 760px;
    margin: 0 auto;
    padding: 0 var(--space-6);
}
.lib-hero-badge {
    display: inline-flex;
    align-items: center;
    gap: var(--space-2);
    padding: var(--space-1) var(--space-5);
    background: rgba(255,255,255,0.08);
    border: 1px solid rgba(255,255,255,0.14);
    border-radius: var(--radius-full);
    font-size: var(--text-xs);
    font-weight: 600;
    color: rgba(255,255,255,0.85);
    margin-bottom: var(--space-6);
    letter-spacing: 0.06em;
    text-transform: uppercase;
}
.lib-hero h1 {
    font-size: clamp(2rem, 5vw, 3rem);
    font-weight: 800;
    color: #ffffff;
    letter-spacing: -0.03em;
    line-height: 1.1;
    margin-bottom: var(--space-4);
}
.lib-hero h1 span {
    background: linear-gradient(135deg, var(--primary-300) 0%, #00d4ff 50%, var(--accent-400) 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}
.lib-hero p {
    font-size: var(--text-lg);
    color: rgba(255,255,255,0.65);
    margin-bottom: var(--space-8);
    line-height: 1.7;
}

/* Search Bar */
.search-wrapper {
    position: relative;
    max-width: 640px;
    margin: 0 auto;
}
.search-icon {
    position: absolute;
    left: 18px;
    top: 50%;
    transform: translateY(-50%);
    color: rgba(255,255,255,0.45);
    font-size: 18px;
    pointer-events: none;
}
#searchInput {
    width: 100%;
    padding: 16px 52px 16px 52px;
    font-size: var(--text-base);
    font-family: var(--font-sans);
    background: rgba(255,255,255,0.08);
    border: 1.5px solid rgba(255,255,255,0.18);
    border-radius: var(--radius-full);
    color: #fff;
    backdrop-filter: blur(12px);
    transition: all var(--transition-base);
    outline: none;
}
#searchInput::placeholder { color: rgba(255,255,255,0.4); }
#searchInput:focus {
    border-color: var(--primary-400);
    background: rgba(255,255,255,0.12);
    box-shadow: 0 0 0 4px rgba(51,129,255,0.18);
}
.search-clear {
    position: absolute;
    right: 16px;
    top: 50%;
    transform: translateY(-50%);
    background: rgba(255,255,255,0.15);
    border: none;
    border-radius: 50%;
    width: 26px;
    height: 26px;
    cursor: pointer;
    color: rgba(255,255,255,0.7);
    font-size: 14px;
    display: none;
    align-items: center;
    justify-content: center;
    transition: all var(--transition-fast);
}
.search-clear:hover { background: rgba(255,255,255,0.25); }
.search-clear.visible { display: flex; }

/* Hero stats ribbon */
.lib-stats-ribbon {
    display: flex;
    justify-content: center;
    gap: var(--space-8);
    margin-top: var(--space-8);
    flex-wrap: wrap;
}
.lib-stat-item {
    text-align: center;
}
.lib-stat-item strong {
    display: block;
    font-size: var(--text-2xl);
    font-weight: 800;
    color: #fff;
}
.lib-stat-item span {
    font-size: var(--text-xs);
    color: rgba(255,255,255,0.5);
    text-transform: uppercase;
    letter-spacing: 0.06em;
}

/* ===== Filters & Controls ===== */
.lib-controls {
    background: var(--bg-secondary);
    border-bottom: 1px solid var(--border-light);
    padding: var(--space-4) 0;
    position: sticky;
    top: var(--header-height);
    z-index: 90;
    backdrop-filter: blur(12px);
}
.lib-controls-inner {
    display: flex;
    gap: var(--space-3);
    align-items: center;
    flex-wrap: wrap;
}

/* Filter pills */
.filter-group {
    display: flex;
    gap: var(--space-2);
    align-items: center;
    flex-wrap: wrap;
}
.filter-label {
    font-size: var(--text-xs);
    font-weight: 600;
    color: var(--text-tertiary);
    text-transform: uppercase;
    letter-spacing: 0.06em;
    white-space: nowrap;
}
.filter-pill {
    display: inline-flex;
    align-items: center;
    gap: 5px;
    padding: 5px 13px;
    font-size: var(--text-xs);
    font-weight: 600;
    border: 1.5px solid var(--border-light);
    border-radius: var(--radius-full);
    background: var(--bg-primary);
    color: var(--text-secondary);
    cursor: pointer;
    transition: all var(--transition-fast);
    white-space: nowrap;
    user-select: none;
}
.filter-pill:hover {
    border-color: var(--primary-400);
    color: var(--primary);
    background: var(--primary-50);
}
.filter-pill.active {
    background: var(--primary);
    border-color: var(--primary);
    color: #fff;
}
[data-theme="dark"] .filter-pill:hover { background: rgba(51,129,255,0.1); }
[data-theme="dark"] .filter-pill.active { background: var(--primary-600); }

/* Sort selector */
.sort-select {
    padding: 6px 12px;
    font-size: var(--text-xs);
    font-weight: 600;
    font-family: var(--font-sans);
    border: 1.5px solid var(--border-light);
    border-radius: var(--radius-full);
    background: var(--bg-primary);
    color: var(--text-primary);
    cursor: pointer;
    outline: none;
    transition: border-color var(--transition-fast);
}
.sort-select:focus { border-color: var(--primary-400); }

.controls-spacer { flex: 1; }

/* Results count */
.results-count {
    font-size: var(--text-sm);
    color: var(--text-tertiary);
    white-space: nowrap;
}
.results-count strong { color: var(--text-primary); }

/* Divider pill */
.filter-divider {
    width: 1px;
    height: 22px;
    background: var(--border-light);
    flex-shrink: 0;
}

/* ===== Main Library Layout ===== */
.lib-body {
    background: var(--bg-primary);
    min-height: 60vh;
    padding: var(--space-8) 0 var(--space-16);
}
.lib-body-inner {
    display: grid;
    grid-template-columns: 240px 1fr;
    gap: var(--space-8);
    align-items: start;
}

/* ===== Sidebar ===== */
.lib-sidebar {
    position: sticky;
    top: calc(var(--header-height) + 64px);
}
.sidebar-section {
    background: var(--bg-secondary);
    border: 1px solid var(--border-light);
    border-radius: var(--radius-lg);
    padding: var(--space-5);
    margin-bottom: var(--space-4);
}
.sidebar-title {
    font-size: var(--text-xs);
    font-weight: 700;
    color: var(--text-tertiary);
    text-transform: uppercase;
    letter-spacing: 0.08em;
    margin-bottom: var(--space-3);
}
.sidebar-option {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 7px 10px;
    border-radius: var(--radius-md);
    cursor: pointer;
    transition: all var(--transition-fast);
    margin-bottom: 2px;
}
.sidebar-option:hover { background: var(--bg-tertiary); }
.sidebar-option.active {
    background: linear-gradient(135deg, rgba(51,129,255,0.1), rgba(51,129,255,0.05));
    border: 1px solid rgba(51,129,255,0.2);
}
.sidebar-option-left {
    display: flex;
    align-items: center;
    gap: var(--space-2);
    font-size: var(--text-sm);
    font-weight: 500;
    color: var(--text-secondary);
}
.sidebar-option.active .sidebar-option-left { color: var(--primary); font-weight: 600; }
.sidebar-option-icon { font-size: 15px; }
.sidebar-badge {
    font-size: 10px;
    font-weight: 700;
    padding: 2px 7px;
    border-radius: var(--radius-full);
    background: var(--bg-tertiary);
    color: var(--text-tertiary);
}
.sidebar-option.active .sidebar-badge {
    background: rgba(51,129,255,0.15);
    color: var(--primary);
}

/* ===== Calculator Cards Grid ===== */
.calc-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
    gap: var(--space-5);
}

/* Empty state */
.empty-state {
    grid-column: 1 / -1;
    text-align: center;
    padding: var(--space-16) var(--space-8);
}
.empty-state .empty-icon { font-size: 4rem; margin-bottom: var(--space-4); }
.empty-state h3 { font-size: var(--text-xl); color: var(--text-secondary); margin-bottom: var(--space-2); }
.empty-state p { color: var(--text-tertiary); font-size: var(--text-sm); }

/* ===== Calculator Card ===== */
.calc-card {
    background: var(--card-bg);
    border: 1px solid var(--card-border);
    border-radius: var(--radius-lg);
    padding: var(--space-5);
    text-decoration: none;
    display: flex;
    flex-direction: column;
    gap: var(--space-3);
    transition: all var(--transition-base);
    position: relative;
    overflow: hidden;
    cursor: pointer;
}
.calc-card::before {
    content: '';
    position: absolute;
    top: 0; left: 0; right: 0;
    height: 3px;
    opacity: 0;
    transition: opacity var(--transition-base);
}
.calc-card:hover {
    border-color: var(--card-hover-border);
    box-shadow: var(--card-hover-shadow);
    transform: translateY(-3px);
}
.calc-card:hover::before { opacity: 1; }

/* Discipline color accent lines */
.calc-card[data-discipline="conduction"]::before { background: linear-gradient(90deg, #f97316, #fb923c); }
.calc-card[data-discipline="convection"]::before { background: linear-gradient(90deg, #3b82f6, #60a5fa); }
.calc-card[data-discipline="heat-exchangers"]::before { background: linear-gradient(90deg, #8b5cf6, #a78bfa); }
.calc-card[data-discipline="fluid-mechanics"]::before { background: linear-gradient(90deg, #06b6d4, #22d3ee); }
.calc-card[data-discipline="thermodynamics"]::before { background: linear-gradient(90deg, #10b981, #34d399); }
.calc-card[data-discipline="tools"]::before { background: linear-gradient(90deg, #6b7280, #9ca3af); }
.calc-card[data-discipline="radiation"]::before { background: linear-gradient(90deg, #fbbf24, #f59e0b); }
.calc-card[data-discipline="mass-transfer"]::before { background: linear-gradient(90deg, #ec4899, #f472b6); }
.calc-card[data-discipline="cfd"]::before { background: linear-gradient(90deg, #8b5cf6, #a78bfa); }


.card-header {
    display: flex;
    align-items: flex-start;
    justify-content: space-between;
    gap: var(--space-3);
}
.card-icon-wrap {
    width: 46px;
    height: 46px;
    border-radius: var(--radius-md);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 22px;
    flex-shrink: 0;
}
/* Icon backgrounds per discipline */
.calc-card[data-discipline="conduction"] .card-icon-wrap { background: linear-gradient(135deg, #fff7ed, #fed7aa); }
.calc-card[data-discipline="convection"] .card-icon-wrap { background: linear-gradient(135deg, #eff6ff, #bfdbfe); }
.calc-card[data-discipline="heat-exchangers"] .card-icon-wrap { background: linear-gradient(135deg, #f5f3ff, #ddd6fe); }
.calc-card[data-discipline="fluid-mechanics"] .card-icon-wrap { background: linear-gradient(135deg, #ecfeff, #a5f3fc); }
.calc-card[data-discipline="thermodynamics"] .card-icon-wrap { background: linear-gradient(135deg, #ecfdf5, #a7f3d0); }
.calc-card[data-discipline="tools"] .card-icon-wrap { background: linear-gradient(135deg, #f9fafb, #e5e7eb); }
.calc-card[data-discipline="radiation"] .card-icon-wrap { background: linear-gradient(135deg, #fef3c7, #fde68a); }
.calc-card[data-discipline="mass-transfer"] .card-icon-wrap { background: linear-gradient(135deg, #fdf2f8, #fbcfe8); }
.calc-card[data-discipline="cfd"] .card-icon-wrap { background: linear-gradient(135deg, #f5f3ff, #ddd6fe); }


[data-theme="dark"] .calc-card[data-discipline="conduction"] .card-icon-wrap { background: linear-gradient(135deg, #431407, #7c2d12); }
[data-theme="dark"] .calc-card[data-discipline="convection"] .card-icon-wrap { background: linear-gradient(135deg, #1e3a5f, #1d4ed8); }
[data-theme="dark"] .calc-card[data-discipline="heat-exchangers"] .card-icon-wrap { background: linear-gradient(135deg, #2e1065, #4c1d95); }
[data-theme="dark"] .calc-card[data-discipline="fluid-mechanics"] .card-icon-wrap { background: linear-gradient(135deg, #083344, #155e75); }
[data-theme="dark"] .calc-card[data-discipline="thermodynamics"] .card-icon-wrap { background: linear-gradient(135deg, #022c22, #064e3b); }
[data-theme="dark"] .calc-card[data-discipline="tools"] .card-icon-wrap { background: linear-gradient(135deg, #111827, #1f2937); }
[data-theme="dark"] .calc-card[data-discipline="radiation"] .card-icon-wrap { background: linear-gradient(135deg, #78350f, #92400e); }
[data-theme="dark"] .calc-card[data-discipline="mass-transfer"] .card-icon-wrap { background: linear-gradient(135deg, #500724, #831843); }
[data-theme="dark"] .calc-card[data-discipline="cfd"] .card-icon-wrap { background: linear-gradient(135deg, #2e1065, #4c1d95); }


.card-badges {
    display: flex;
    flex-direction: column;
    align-items: flex-end;
    gap: 4px;
}
.card-badge {
    display: inline-flex;
    align-items: center;
    gap: 4px;
    font-size: 10px;
    font-weight: 700;
    padding: 3px 8px;
    border-radius: var(--radius-full);
    white-space: nowrap;
    letter-spacing: 0.04em;
    text-transform: uppercase;
}
.badge-popular { background: rgba(249,115,22,0.12); color: #ea580c; border: 1px solid rgba(249,115,22,0.2); }
.badge-new { background: rgba(16,185,129,0.12); color: #059669; border: 1px solid rgba(16,185,129,0.2); }
.badge-coming { background: rgba(107,114,128,0.12); color: #6b7280; border: 1px solid rgba(107,114,128,0.2); }
.badge-beginner { background: rgba(59,130,246,0.12); color: #2563eb; border: 1px solid rgba(59,130,246,0.2); }
.badge-advanced { background: rgba(139,92,246,0.12); color: #7c3aed; border: 1px solid rgba(139,92,246,0.2); }
.badge-verified { background: rgba(16,185,129,0.1); color: #059669; border: 1px solid rgba(16,185,129,0.2); }

.card-title {
    font-size: var(--text-base);
    font-weight: 700;
    color: var(--text-primary);
    line-height: 1.3;
}
.card-desc {
    font-size: var(--text-sm);
    color: var(--text-secondary);
    line-height: 1.55;
    margin: 0;
    flex: 1;
}
.card-meta {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: var(--space-2);
    padding-top: var(--space-3);
    border-top: 1px solid var(--border-light);
    flex-wrap: wrap;
}
.card-discipline-tag {
    display: inline-flex;
    align-items: center;
    gap: 5px;
    font-size: 11px;
    font-weight: 600;
    color: var(--text-tertiary);
}
.card-discipline-dot {
    width: 6px;
    height: 6px;
    border-radius: 50%;
    flex-shrink: 0;
}
.calc-card[data-discipline="conduction"] .card-discipline-dot { background: #f97316; }
.calc-card[data-discipline="convection"] .card-discipline-dot { background: #3b82f6; }
.calc-card[data-discipline="heat-exchangers"] .card-discipline-dot { background: #8b5cf6; }
.calc-card[data-discipline="fluid-mechanics"] .card-discipline-dot { background: #06b6d4; }
.calc-card[data-discipline="thermodynamics"] .card-discipline-dot { background: #10b981; }
.calc-card[data-discipline="tools"] .card-discipline-dot { background: #6b7280; }
.calc-card[data-discipline="radiation"] .card-discipline-dot { background: #eab308; }
.calc-card[data-discipline="mass-transfer"] .card-discipline-dot { background: #ec4899; }
.calc-card[data-discipline="cfd"] .card-discipline-dot { background: #8b5cf6; }


.card-apps {
    display: flex;
    gap: 4px;
    flex-wrap: wrap;
}
.card-app-tag {
    font-size: 10px;
    padding: 2px 7px;
    border-radius: var(--radius-full);
    background: var(--bg-tertiary);
    color: var(--text-tertiary);
    font-weight: 500;
}
.card-arrow {
    font-size: 14px;
    color: var(--text-tertiary);
    transition: all var(--transition-fast);
}
.calc-card:hover .card-arrow {
    color: var(--primary);
    transform: translateX(3px);
}

/* Coming soon overlay */
.calc-card.coming-soon {
    opacity: 0.65;
    cursor: default;
    pointer-events: none;
}
.calc-card.coming-soon:hover {
    transform: none;
    box-shadow: none;
    border-color: var(--card-border);
}

/* ===== Section Headers in grid ===== */
.section-divider {
    grid-column: 1 / -1;
    display: flex;
    align-items: center;
    gap: var(--space-3);
    padding: var(--space-2) 0;
    margin-top: var(--space-4);
}
.section-divider:first-child { margin-top: 0; }
.section-divider h2 {
    font-size: var(--text-sm);
    font-weight: 700;
    color: var(--text-tertiary);
    text-transform: uppercase;
    letter-spacing: 0.08em;
    white-space: nowrap;
}
.section-divider-line {
    flex: 1;
    height: 1px;
    background: var(--border-light);
}
.section-divider-count {
    font-size: 11px;
    font-weight: 600;
    color: var(--text-tertiary);
    background: var(--bg-tertiary);
    padding: 2px 10px;
    border-radius: var(--radius-full);
}

/* ===== Responsive ===== */
@media (max-width: 960px) {
    .lib-body-inner {
        grid-template-columns: 1fr;
    }
    .lib-sidebar {
        position: static;
        display: grid;
        grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
        gap: var(--space-3);
    }
}
@media (max-width: 680px) {
    .calc-grid { grid-template-columns: 1fr; }
    .lib-controls-inner { gap: var(--space-2); }
    .lib-stats-ribbon { gap: var(--space-5); }
}

/* ===== Dashboard Portal Styles ===== */
.lib-dashboard {
    margin-bottom: var(--space-10);
}
.dashboard-section {
    margin-bottom: var(--space-10);
}
.dashboard-section-title {
    font-size: var(--text-lg);
    font-weight: 700;
    color: var(--text-primary);
    margin-bottom: var(--space-5);
    display: flex;
    align-items: center;
    gap: 8px;
    border-bottom: 2px solid var(--border-light);
    padding-bottom: 10px;
}

/* Popular grid */
.popular-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
    gap: var(--space-4);
}
.popular-card {
    background: var(--card-bg);
    border: 1px solid var(--card-border);
    border-radius: var(--radius-md);
    padding: var(--space-4);
    text-decoration: none;
    display: flex;
    align-items: center;
    gap: var(--space-3);
    transition: all var(--transition-base);
    position: relative;
    overflow: hidden;
}
.popular-card:hover {
    border-color: var(--primary-400);
    transform: translateY(-2px);
    box-shadow: var(--shadow-sm);
}
.popular-card-icon {
    font-size: 24px;
    width: 48px;
    height: 48px;
    border-radius: var(--radius-md);
    background: var(--bg-tertiary);
    display: flex;
    align-items: center;
    justify-content: center;
    flex-shrink: 0;
}
.popular-card-info {
    flex: 1;
    min-width: 0;
}
.popular-card-title {
    font-size: var(--text-sm);
    font-weight: 700;
    color: var(--text-primary);
    margin-bottom: 2px;
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
}
.popular-card-desc {
    font-size: var(--text-xs);
    color: var(--text-secondary);
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
    margin: 0;
}

/* Discipline Cards Grid */
.discipline-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
    gap: var(--space-5);
}
.discipline-portal-card {
    background: var(--card-bg);
    border: 1px solid var(--card-border);
    border-radius: var(--radius-lg);
    padding: var(--space-5);
    text-decoration: none;
    display: flex;
    flex-direction: column;
    gap: var(--space-3);
    transition: all var(--transition-base);
    position: relative;
    overflow: hidden;
}
.discipline-portal-card::after {
    content: '';
    position: absolute;
    bottom: 0; left: 0; right: 0;
    height: 4px;
    background: var(--border-light);
    transition: background var(--transition-base);
}
.discipline-portal-card:hover {
    transform: translateY(-3px);
    box-shadow: var(--card-hover-shadow);
    border-color: var(--card-hover-border);
}
.discipline-portal-card.heat:hover::after { background: var(--primary); }
.discipline-portal-card.fluid:hover::after { background: #06b6d4; }
.discipline-portal-card.thermo:hover::after { background: #10b981; }
.discipline-portal-card.cfd:hover::after { background: #8b5cf6; }
.discipline-portal-card.mass:hover::after { background: #ec4899; }
.discipline-portal-card.hvac:hover::after { background: #3b82f6; }
.discipline-portal-card.process:hover::after { background: #f59e0b; }
.discipline-portal-card.tools:hover::after { background: #6b7280; }

.discipline-portal-icon {
    width: 44px;
    height: 44px;
    border-radius: var(--radius-md);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 20px;
}
.discipline-portal-card.heat .discipline-portal-icon { background: rgba(249,115,22,0.1); color: #f97316; }
.discipline-portal-card.fluid .discipline-portal-icon { background: rgba(6,182,212,0.1); color: #06b6d4; }
.discipline-portal-card.thermo .discipline-portal-icon { background: rgba(16,185,129,0.1); color: #10b981; }
.discipline-portal-card.cfd .discipline-portal-icon { background: rgba(139,92,246,0.1); color: #8b5cf6; }
.discipline-portal-card.mass .discipline-portal-icon { background: rgba(236,72,153,0.1); color: #ec4899; }
.discipline-portal-card.hvac .discipline-portal-icon { background: rgba(59,130,246,0.1); color: #3b82f6; }
.discipline-portal-card.process .discipline-portal-icon { background: rgba(245,158,11,0.1); color: #f59e0b; }
.discipline-portal-card.tools .discipline-portal-icon { background: rgba(107,114,128,0.1); color: #6b7280; }

.discipline-portal-title {
    font-size: var(--text-base);
    font-weight: 700;
    color: var(--text-primary);
    display: flex;
    align-items: center;
    justify-content: space-between;
}
.discipline-portal-count {
    font-size: var(--text-xs);
    font-weight: 600;
    color: var(--text-tertiary);
    background: var(--bg-tertiary);
    padding: 2px 8px;
    border-radius: var(--radius-full);
}
.discipline-portal-desc {
    font-size: var(--text-sm);
    color: var(--text-secondary);
    line-height: 1.5;
    margin: 0;
}

/* Recently Added Grid */
.recent-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: var(--space-4);
}