:root {
    --ink: #111111;
    --muted: #555555;
    --paper: #eeeae0;
    --card: #ffffff;
    --line: #d5d0c5;
    --shadow: 3px 3px 0 #111;
    --bio: #005e22;
    --bio-soft: #dff0e4;
    --chem: #c8001e;
    --chem-soft: #fde8eb;
    --phys: #d08000;
    --phys-soft: #fef0cc;
    --accent: #2255cc;
    --amber: #d08000;
    --red: #c8001e;
    --green: #005e22;
    --sticky-offset: 170px;
    --science-deep: #111111;
    --science-mid: #1a3a1a;
    --science-bright: #005e22;
    --science-mist: #dff0e4;
    --science-accent: #00a03a;
}

* {
    box-sizing: border-box;
}

html {
    scroll-padding-top: var(--sticky-offset);
}

body {
    margin: 0;
    font-family: 'Barlow', "Segoe UI", Tahoma, Geneva, Verdana, sans-serif;
    color: var(--ink);
    background: var(--paper);
    min-height: 100vh;
}

body[data-subject="science"] {
    background: var(--paper);
}

.spec-shell {
    max-width: 1300px;
    margin: 0 auto;
    padding: 10px 18px 36px;
    position: relative;
}

.spec-topbar {
    position: static;
    display: flex;
    flex-wrap: wrap;
    gap: 8px;
    align-items: center;
    justify-content: space-between;
    padding: 0;
    border-radius: 0;
    background: transparent;
    box-shadow: none;
    border: none;
    margin-bottom: 8px;
}

.topbar-left,
.topbar-right {
    display: flex;
    flex-wrap: wrap;
    align-items: center;
    gap: 8px;
}

.topbar-right {
    justify-content: flex-end;
}

.topbar-link {
    text-decoration: none;
    color: var(--ink);
    background: white;
    border: 2px solid var(--ink);
    padding: 5px 12px;
    border-radius: 0;
    font-size: 12px;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 0.5px;
    transition: background 0.15s ease, color 0.15s ease;
}

.topbar-link:hover {
    background: var(--ink);
    color: #eeeae0;
}

.topbar-link.subject-bio {
    background: var(--bio-soft);
    border-color: var(--bio);
    color: var(--bio);
}

.topbar-link.subject-chem {
    background: var(--chem-soft);
    border-color: var(--chem);
    color: var(--chem);
}

.topbar-link.subject-phys {
    background: var(--phys-soft);
    border-color: var(--phys);
    color: var(--phys);
}

.auth-status {
    font-size: 11px;
    color: #1f2937;
}

.auth-button {
    border: none;
    padding: 6px 12px;
    border-radius: 999px;
    font-weight: 600;
    font-size: 11px;
    color: #ffffff;
    background: rgba(15, 23, 42, 0.9);
    cursor: pointer;
    transition: transform 0.2s ease, box-shadow 0.2s ease;
}

.auth-button:hover {
    transform: translateY(-1px);
    box-shadow: 0 8px 18px rgba(15, 23, 42, 0.2);
}

.auth-button.secondary {
    background: #475569;
}

.auth-button.hidden {
    display: none;
}

.progress-summary-button {
    background: rgba(255, 255, 255, 0.2);
    color: #f8fafc;
    border: 1px solid rgba(255, 255, 255, 0.45);
}

.spec-hero {
    margin-top: 0;
    padding: 14px 18px;
    border-radius: 0;
    color: #ffffff;
    box-shadow: none;
    border-bottom: 4px solid rgba(0,0,0,0.3);
    position: sticky;
    top: 0;
    overflow: hidden;
    z-index: 20;
    display: flex;
    justify-content: space-between;
    gap: 16px;
}

.hero-left {
    min-width: 0;
    display: flex;
    flex-direction: column;
    gap: 8px;
}

.hero-right {
    display: flex;
    flex-direction: column;
    align-items: flex-end;
    gap: 8px;
}

.hero-actions {
    display: flex;
    flex-wrap: wrap;
    align-items: center;
    gap: 8px;
}

.hero-progress-inline {
    display: inline-flex;
    align-items: center;
    gap: 8px;
}

.spec-hero::after {
    content: none;
}

.spec-hero h1 {
    margin: 0 0 4px;
    font-size: 28px;
    letter-spacing: -0.5px;
}

.spec-hero p {
    margin: 0;
    font-size: 14px;
    opacity: 0.9;
}

.spec-hero.biology  { background: #005e22; }
.spec-hero.chemistry { background: #c8001e; }
.spec-hero.physics   { background: #d08000; }

.science-hero {
    margin-top: 8px;
    padding: 32px;
    border-radius: 0;
    background: #111;
    color: #eeeae0;
    box-shadow: none;
    border-left: 8px solid #005e22;
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 24px;
    position: relative;
    overflow: hidden;
    animation: rise-in 0.6s ease both;
}

.science-hero::before { content: none; }

.science-hero-copy {
    display: flex;
    flex-direction: column;
    gap: 14px;
    z-index: 1;
}

.hero-eyebrow {
    text-transform: uppercase;
    letter-spacing: 2px;
    font-size: 11px;
    font-weight: 700;
    color: rgba(255, 255, 255, 0.75);
}

.science-hero h1 {
    margin: 0;
    font-family: "Fraunces", "Space Grotesk", "Segoe UI", sans-serif;
    font-size: clamp(30px, 4vw, 44px);
    line-height: 1.1;
    letter-spacing: -0.6px;
}

.hero-lede {
    margin: 0;
    font-size: 16px;
    color: rgba(248, 250, 252, 0.85);
}

.hero-actions {
    display: flex;
    flex-wrap: wrap;
    gap: 10px;
}

.hero-toggle {
    display: inline-flex;
    align-items: center;
    background: rgba(15, 23, 42, 0.25);
    border-radius: 999px;
    padding: 4px;
    border: 1px solid rgba(255, 255, 255, 0.25);
    gap: 4px;
}

.hero-toggle-button {
    border: none;
    background: transparent;
    color: rgba(248, 250, 252, 0.8);
    font-size: 11px;
    font-weight: 700;
    padding: 6px 12px;
    border-radius: 999px;
    cursor: pointer;
    transition: background 0.2s ease, color 0.2s ease;
}

.hero-toggle-button.is-active {
    background: #f8fafc;
    color: #0f172a;
}

.hero-button {
    border: 1px solid transparent;
    border-radius: 999px;
    padding: 8px 16px;
    font-weight: 700;
    font-size: 12px;
    letter-spacing: 0.2px;
    cursor: pointer;
    text-decoration: none;
    transition: transform 0.2s ease, box-shadow 0.2s ease;
    background: rgba(255, 255, 255, 0.15);
    color: #f8fafc;
    display: inline-flex;
    align-items: center;
    justify-content: center;
}

.hero-button.primary {
    background: var(--science-accent);
    color: #3b2a12;
}

.hero-button.ghost {
    border-color: rgba(255, 255, 255, 0.35);
}

.hero-button.outline {
    border-color: rgba(255, 255, 255, 0.6);
    background: rgba(15, 23, 42, 0.2);
}

.hero-button:hover {
    transform: translateY(-1px);
    box-shadow: 0 12px 24px rgba(5, 16, 26, 0.25);
}

.hero-note {
    margin: 0;
    font-size: 12px;
    color: rgba(226, 232, 240, 0.9);
}

.science-hero-panel {
    background: rgba(255, 255, 255, 0.95);
    border-radius: 20px;
    padding: 18px;
    color: var(--ink);
    box-shadow: 0 18px 36px rgba(11, 24, 38, 0.25);
    z-index: 1;
    display: flex;
    flex-direction: column;
    gap: 12px;
}

.panel-title {
    font-weight: 700;
    font-size: 14px;
}

.progress-mini-grid {
    display: grid;
    gap: 12px;
}

.progress-mini-card {
    background: var(--science-mist);
    border-radius: 14px;
    padding: 12px;
    border: 1px solid rgba(15, 23, 42, 0.08);
    display: grid;
    gap: 8px;
    text-decoration: none;
    color: inherit;
    transition: transform 0.2s ease, box-shadow 0.2s ease;
}

.progress-mini-card:hover {
    transform: translateY(-2px);
    box-shadow: 0 14px 28px rgba(15, 23, 42, 0.15);
}

.progress-mini-card.is-empty {
    background: rgba(248, 250, 252, 0.6);
}

.progress-mini-head {
    display: flex;
    justify-content: space-between;
    align-items: center;
    gap: 8px;
}

.progress-mini-title {
    font-weight: 700;
    font-size: 13px;
}

.progress-mini-mode {
    font-size: 11px;
    color: var(--muted);
}

.progress-mini-bar {
    display: flex;
    background: rgba(15, 23, 42, 0.08);
    border-radius: 999px;
    overflow: hidden;
    height: 10px;
}

.progress-mini-bar .bar-seg {
    height: 100%;
    display: block;
    width: 0;
}

.bar-seg.is-green {
    background: #16a34a;
}

.bar-seg.is-amber {
    background: #f59e0b;
}

.bar-seg.is-red {
    background: #ef4444;
}

.progress-mini-meta {
    font-size: 12px;
    color: var(--muted);
}

.science-steps,
.science-pathways {
    margin-top: 24px;
}

.section-title {
    display: grid;
    gap: 6px;
    margin-bottom: 14px;
}

.section-title h2 {
    margin: 0;
    font-size: 22px;
}

.section-title p {
    margin: 0;
    color: var(--muted);
    font-size: 14px;
}

.step-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
    gap: 16px;
}

.step-card {
    background: #ffffff;
    border-radius: 18px;
    padding: 18px;
    border: 1px solid rgba(15, 23, 42, 0.08);
    box-shadow: 0 16px 34px rgba(15, 23, 42, 0.08);
    position: relative;
    overflow: hidden;
    animation: rise-in 0.6s ease both;
}

.step-card::after {
    content: "";
    position: absolute;
    inset: 0;
    background: linear-gradient(130deg, rgba(241, 178, 74, 0.2), transparent 60%);
    opacity: 0.6;
}

.step-card h3 {
    margin: 0 0 6px;
    font-size: 16px;
    position: relative;
    z-index: 1;
}

.step-card p {
    margin: 0;
    font-size: 13px;
    color: var(--muted);
    line-height: 1.5;
    position: relative;
    z-index: 1;
}

.landing-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
    gap: 18px;
}

.landing-card {
    background: #ffffff;
    border-radius: 20px;
    padding: 20px;
    border: 1px solid rgba(15, 23, 42, 0.08);
    box-shadow: 0 18px 38px rgba(15, 23, 42, 0.08);
    text-decoration: none;
    color: var(--ink);
    transition: transform 0.2s ease, box-shadow 0.2s ease;
}

.landing-card:hover {
    transform: translateY(-3px);
    box-shadow: 0 24px 44px rgba(15, 23, 42, 0.16);
}

.landing-card h2 {
    margin: 0 0 8px;
    font-size: 20px;
}

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

@keyframes rise-in {
    from {
        opacity: 0;
        transform: translateY(12px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.progress-label {
    font-weight: 600;
    font-size: 13px;
    color: #f8fafc;
}

.progress-toggle {
    display: flex;
    gap: 8px;
}

.progress-toggle button {
    border: 1px solid rgba(255, 255, 255, 0.4);
    background: rgba(255, 255, 255, 0.9);
    padding: 6px 12px;
    border-radius: 999px;
    font-size: 12px;
    font-weight: 600;
    cursor: pointer;
}

.progress-toggle button.is-active {
    background: #0f172a;
    color: #ffffff;
    border-color: #0f172a;
}

.hero-progress-inline .progress-toggle button {
    background: rgba(255, 255, 255, 0.18);
    color: #f8fafc;
    border-color: rgba(255, 255, 255, 0.4);
    box-shadow: 0 6px 16px rgba(15, 23, 42, 0.18);
}

.hero-progress-inline .progress-toggle button.is-active {
    background: #0f172a;
    color: #ffffff;
    border-color: #0f172a;
}

.progress-note {
    color: #e2e8f0;
    font-size: 12px;
}

.subject-section {
    margin-top: 20px;
}

.subject-toc {
    display: flex;
    flex-wrap: wrap;
    gap: 8px;
}

.subject-toc a {
    text-decoration: none;
    font-size: 12px;
    color: var(--ink);
    padding: 6px 12px;
    border-radius: 999px;
    background: rgba(15, 23, 42, 0.06);
    border: 1px solid rgba(15, 23, 42, 0.12);
}

.hero-toc a {
    background: rgba(255, 255, 255, 0.92);
    border-color: rgba(255, 255, 255, 0.9);
    color: #0f172a;
}

.hero-toc a:hover {
    background: #ffffff;
}

.topic-grid {
    display: grid;
    grid-template-columns: 1fr;
    gap: 18px;
}

.topic-card {
    background: var(--card);
    border-radius: 0;
    padding: 18px;
    box-shadow: 3px 3px 0 #111;
    border: 1px solid #ccc;
    column-count: 2;
    column-width: 320px;
    column-gap: 28px;
    column-fill: auto;
}

.topic-title {
    margin: 0 0 12px;
    font-size: 20px;
    column-span: all;
    scroll-margin-top: var(--sticky-offset);
}

.subtopic-title {
    font-size: 13px;
    text-transform: uppercase;
    letter-spacing: 0.6px;
    margin: 16px 0 8px;
    color: var(--muted);
    break-inside: avoid;
}

.spec-list {
    list-style: none;
    padding: 0;
    margin: 0;
}

.spec-item {
    margin-bottom: 10px;
    padding: 10px 12px;
    border-radius: 12px;
    background: #f8fafc;
    border: 1px solid rgba(15, 23, 42, 0.08);
    position: relative;
    padding-right: 110px;
    transition: transform 0.2s ease, box-shadow 0.2s ease, background 0.2s ease;
    cursor: pointer;
    break-inside: avoid;
    list-style: none;
}

.spec-item.column-break {
    break-before: column;
    -webkit-column-break-before: always;
}

.spec-item:hover {
    background: #ffffff;
    box-shadow: 0 10px 24px rgba(15, 23, 42, 0.12);
    transform: translateY(-1px);
}

.spec-item.rag-red {
    background: #fff1f2;
    border-color: #fecdd3;
}

.spec-item.rag-amber {
    background: #fff7ed;
    border-color: #fed7aa;
}

.spec-item.rag-green {
    background: #ecfdf3;
    border-color: #bbf7d0;
}

.spec-item-content {
    font-size: 14px;
    line-height: 1.55;
    color: var(--ink);
}

.spec-progress {
    display: flex;
    flex-direction: column;
    gap: 8px;
    align-items: flex-end;
    position: absolute;
    top: 10px;
    right: 10px;
}

.progress-checkbox {
    display: flex;
    align-items: center;
    gap: 6px;
    font-size: 12px;
    font-weight: 600;
    color: var(--muted);
}

.progress-checkbox input {
    width: 16px;
    height: 16px;
}

.progress-rag {
    display: flex;
    gap: 6px;
}

.progress-rag button {
    border: 1px solid rgba(15, 23, 42, 0.16);
    background: #ffffff;
    padding: 2px 8px;
    border-radius: 999px;
    font-size: 10px;
    font-weight: 700;
    cursor: pointer;
}


.has-tooltip {
    position: relative;
}

.has-tooltip::after {
    content: attr(data-tooltip);
    position: absolute;
    left: 50%;
    bottom: calc(100% + 6px);
    transform: translateX(-50%);
    background: rgba(15, 23, 42, 0.92);
    color: #f8fafc;
    padding: 6px 10px;
    border-radius: 8px;
    font-size: 11px;
    white-space: nowrap;
    opacity: 0;
    pointer-events: none;
    transition: opacity 0.2s ease;
}

.has-tooltip:hover::after {
    opacity: 1;
}

.progress-rag button.is-active[data-rag="red"] {
    background: var(--red);
    color: #ffffff;
    border-color: var(--red);
}

.progress-rag button.is-active[data-rag="amber"] {
    background: var(--amber);
    color: #1f2937;
    border-color: var(--amber);
}

.progress-rag button.is-active[data-rag="green"] {
    background: var(--green);
    color: #ffffff;
    border-color: var(--green);
}

body[data-progress-mode="checkbox"] .progress-rag {
    display: none;
}

body[data-progress-mode="rag"] .progress-checkbox {
    display: none;
}

.inline-label {
    font-weight: 600;
    margin: 8px 0 4px;
    color: var(--ink);
}

.bullet-list {
    margin: 6px 0 8px 18px;
    padding-left: 18px;
    color: var(--ink);
}

.bullet-list li {
    margin: 4px 0;
    font-size: 13px;
}

.practical-tag {
    display: inline-block;
    padding: 2px 8px;
    border-radius: 999px;
    font-size: 10px;
    font-weight: 700;
    letter-spacing: 0.4px;
    background: rgba(15, 23, 42, 0.08);
    margin-right: 6px;
}

.spec-divider {
    border-top: 1px dashed rgba(15, 23, 42, 0.18);
    margin: 12px 0;
    text-align: center;
    column-span: all;
}

footer {
    text-align: center;
    font-size: 12px;
    color: var(--muted);
    padding: 30px 0 10px;
}

@media (max-width: 900px) {
    .science-hero {
        padding: 24px;
    }

    .science-hero-panel {
        order: 2;
    }

    .hero-actions {
        width: 100%;
    }
}

@media (max-width: 520px) {
    .spec-topbar {
        position: static;
    }

    .science-hero {
        padding: 20px;
    }

    .hero-actions {
        flex-direction: column;
        align-items: stretch;
    }

    .hero-button {
        width: 100%;
    }

    .topic-card {
        column-count: 1;
    }

    .spec-item {
        padding-right: 12px;
    }

    .spec-progress {
        position: static;
        flex-direction: row;
        justify-content: flex-start;
        margin-top: 8px;
    }
}

.spec-modal {
    position: fixed;
    inset: 0;
    z-index: 50;
    display: none;
    align-items: center;
    justify-content: center;
}

.spec-modal.is-visible {
    display: flex;
}

.spec-modal-backdrop {
    position: absolute;
    inset: 0;
    background: rgba(15, 23, 42, 0.55);
    backdrop-filter: blur(4px);
}

.spec-modal-card {
    position: relative;
    width: min(900px, 92vw);
    max-height: 85vh;
    overflow: auto;
    background: #ffffff;
    border-radius: 22px;
    padding: 22px;
    box-shadow: 0 30px 70px rgba(15, 23, 42, 0.25);
    z-index: 1;
}

.spec-modal-close {
    position: sticky;
    top: 0;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    border: none;
    background: #0f172a;
    color: #ffffff;
    font-size: 12px;
    font-weight: 700;
    padding: 6px 12px;
    border-radius: 999px;
    cursor: pointer;
    margin-bottom: 12px;
}

.spec-modal .spec-item {
    padding-right: 12px;
    cursor: default;
}

.spec-modal .spec-progress {
    position: static;
    flex-direction: row;
    align-items: center;
    gap: 10px;
    margin-bottom: 12px;
}

.progress-modal {
    position: fixed;
    inset: 0;
    z-index: 60;
    display: none;
    align-items: center;
    justify-content: center;
}

.progress-modal.is-visible {
    display: flex;
}

.progress-modal-card {
    position: relative;
    width: min(680px, 92vw);
    max-height: 85vh;
    overflow: auto;
    background: #ffffff;
    border-radius: 22px;
    padding: 22px;
    box-shadow: 0 30px 70px rgba(15, 23, 42, 0.25);
    z-index: 1;
}

.progress-modal h2 {
    margin: 0 0 12px;
    font-size: 20px;
}

.progress-chart {
    display: grid;
    grid-template-columns: auto 1fr;
    gap: 20px;
    align-items: center;
}

.progress-legend {
    display: grid;
    gap: 8px;
    font-size: 13px;
    color: var(--muted);
}

.progress-legend span {
    display: inline-flex;
    align-items: center;
    gap: 8px;
}

.progress-swatch {
    width: 12px;
    height: 12px;
    border-radius: 4px;
    display: inline-block;
}

body.modal-open {
    overflow: hidden;
}