/* === Reset & Base === */
*, *::before, *::after { margin: 0; padding: 0; box-sizing: border-box; }

:root {
    --bg: #0a0a0f;
    --bg-light: #12121a;
    --surface: #1a1a2e;
    --surface-hover: #222240;
    --border: #2a2a45;
    --text: #e4e4ed;
    --text-muted: #8888a4;
    --primary: #6366f1;
    --primary-light: #818cf8;
    --primary-glow: rgba(99, 102, 241, 0.15);
    --accent: #06b6d4;
    --green: #22c55e;
    --red: #ef4444;
    --yellow: #eab308;
    --gradient: linear-gradient(135deg, #6366f1, #06b6d4);
    --radius: 12px;
    --radius-lg: 20px;
}

html { scroll-behavior: smooth; }

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
    background: var(--bg);
    color: var(--text);
    line-height: 1.7;
    overflow-x: hidden;
}

.container { max-width: 1200px; margin: 0 auto; padding: 0 24px; }

/* === Nav === */
.nav {
    display: flex;
    align-items: center;
    justify-content: flex-start;
    gap: 16px;
    padding: 20px 40px;
    position: fixed;
    top: 0; left: 0; right: 0;
    z-index: 100;
    background: rgba(10, 10, 15, 0.8);
    backdrop-filter: blur(20px);
    border-bottom: 1px solid var(--border);
}

.nav-logo {
    font-size: 1.5rem;
    font-weight: 900;
    background: var(--gradient);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    letter-spacing: -0.03em;
}

/* margin-left: auto keeps links on the right without a wide hit-box over the language switcher */
.nav-links { display: flex; gap: 32px; align-items: center; margin-left: auto; }
.nav-links a {
    color: var(--text-muted);
    text-decoration: none;
    font-size: 0.9rem;
    font-weight: 500;
    transition: color 0.2s;
}
.nav-links a:hover { color: var(--text); }

.nav-cta {
    background: var(--gradient) !important;
    color: white !important;
    padding: 8px 20px;
    border-radius: 8px;
    font-weight: 600 !important;
}

/* Language switcher */
.lang-switcher {
    display: flex;
    align-items: center;
    gap: 4px;
    padding: 4px;
    background: rgba(26, 26, 46, 0.6);
    border: 1px solid var(--border);
    border-radius: 10px;
    flex-shrink: 0;
}
.lang-btn {
    font-family: inherit;
    font-size: 0.72rem;
    font-weight: 700;
    padding: 6px 10px;
    border: none;
    border-radius: 6px;
    cursor: pointer;
    background: transparent;
    color: var(--text-muted);
    transition: color 0.2s, background 0.2s;
}
.lang-btn:hover { color: var(--text); background: var(--surface-hover); }
.lang-btn--active {
    background: var(--primary-glow);
    color: var(--primary-light);
    border: 1px solid rgba(99, 102, 241, 0.35);
}

body.lang-zh {
    font-family: 'Noto Sans SC', 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
}
body.lang-zh .spec-code,
body.lang-zh .gs-code,
body.lang-zh .spec-filename {
    font-family: 'JetBrains Mono', 'Noto Sans SC', monospace;
}

.nav-toggle { display: none; background: none; border: none; cursor: pointer; }
.nav-toggle span {
    display: block; width: 24px; height: 2px;
    background: var(--text); margin: 5px 0;
    transition: 0.3s;
}

/* === Hero === */
.hero {
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    text-align: center;
    padding: 120px 24px 60px;
    position: relative;
    overflow: hidden;
    background-size: cover;
    background-position: center;
    background-repeat: no-repeat;
}

.nav-logo-img { height: 36px; width: auto; display: block; }

.hero::before {
    content: '';
    position: absolute;
    inset: 0;
    background: rgba(10, 10, 15, 0.75);
    z-index: 0;
}

.hero::after {
    content: '';
    position: absolute;
    top: -50%; left: -50%;
    width: 200%; height: 200%;
    background: radial-gradient(circle at 50% 50%, var(--primary-glow), transparent 50%);
    animation: pulse 8s ease-in-out infinite;
    z-index: 0;
}

@keyframes pulse {
    0%, 100% { opacity: 0.3; transform: scale(1); }
    50% { opacity: 0.6; transform: scale(1.1); }
}

.hero-content { position: relative; z-index: 1; max-width: 800px; }

.hero-badge {
    display: inline-block;
    padding: 6px 16px;
    border-radius: 20px;
    background: var(--primary-glow);
    border: 1px solid rgba(99, 102, 241, 0.3);
    color: var(--primary-light);
    font-size: 0.85rem;
    font-weight: 600;
    margin-bottom: 24px;
    letter-spacing: 0.02em;
}

.hero h1 {
    font-size: clamp(2.5rem, 6vw, 4.5rem);
    font-weight: 900;
    line-height: 1.1;
    letter-spacing: -0.04em;
    margin-bottom: 24px;
}

.gradient-text {
    background: var(--gradient);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.hero-subtitle {
    font-size: 1.2rem;
    color: var(--text-muted);
    max-width: 600px;
    margin: 0 auto 40px;
    line-height: 1.8;
}

.hero-ctas { display: flex; gap: 16px; justify-content: center; flex-wrap: wrap; }

.btn {
    padding: 14px 32px;
    border-radius: 10px;
    font-size: 1rem;
    font-weight: 600;
    text-decoration: none;
    transition: all 0.3s;
    display: inline-block;
}

.btn-primary {
    background: var(--gradient);
    color: white;
    border: none;
}
.btn-primary:hover { transform: translateY(-2px); box-shadow: 0 8px 30px var(--primary-glow); }

.btn-outline {
    background: transparent;
    color: var(--text);
    border: 1px solid var(--border);
}
.btn-outline:hover { border-color: var(--primary); background: var(--primary-glow); }

/* Flow Diagram */
.hero-visual {
    position: relative;
    z-index: 1;
    margin-top: 60px;
    width: 100%;
    max-width: 1000px;
}

.flow-diagram {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    flex-wrap: wrap;
    padding: 32px 24px;
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: var(--radius-lg);
}

.flow-step {
    text-align: center;
    padding: 16px 12px;
    border-radius: var(--radius);
    transition: all 0.3s;
    min-width: 90px;
}
.flow-step:hover { background: var(--surface-hover); transform: translateY(-4px); }
.flow-icon { font-size: 2rem; margin-bottom: 8px; }
.flow-label { font-weight: 700; font-size: 0.85rem; }
.flow-desc { font-size: 0.75rem; color: var(--text-muted); margin-top: 4px; }
.flow-arrow { color: var(--primary-light); font-size: 1.5rem; font-weight: 300; }

/* === Sections === */
.section { padding: 120px 0; }
.section-dark { background: var(--bg-light); }

.section-header {
    text-align: center;
    max-width: 700px;
    margin: 0 auto 64px;
}

.section-badge {
    display: inline-block;
    padding: 4px 14px;
    border-radius: 16px;
    background: var(--primary-glow);
    border: 1px solid rgba(99, 102, 241, 0.2);
    color: var(--primary-light);
    font-size: 0.8rem;
    font-weight: 600;
    margin-bottom: 16px;
    text-transform: uppercase;
    letter-spacing: 0.05em;
}

.section-header h2 {
    font-size: clamp(2rem, 4vw, 3rem);
    font-weight: 800;
    letter-spacing: -0.03em;
    line-height: 1.2;
    margin-bottom: 16px;
}

.section-subtitle {
    font-size: 1.1rem;
    color: var(--text-muted);
    line-height: 1.7;
}

/* === Section Images === */
.section-image {
    max-width: 800px;
    margin: 0 auto 48px;
    border-radius: var(--radius-lg);
    overflow: hidden;
    border: 1px solid var(--border);
}

.section-image img {
    width: 100%;
    height: auto;
    display: block;
    transition: transform 0.5s ease;
}

.section-image:hover img { transform: scale(1.02); }

/* === Paradigm Grid === */
.paradigm-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 20px; margin-bottom: 48px; }

.paradigm-card {
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    padding: 32px 24px;
    text-align: center;
    transition: all 0.3s;
}
.paradigm-card:hover { border-color: var(--primary); transform: translateY(-4px); }

.paradigm-highlight {
    background: var(--primary-glow);
    border-color: var(--primary) !important;
    position: relative;
}

.paradigm-name { font-size: 1.8rem; font-weight: 900; margin-bottom: 4px; }
.paradigm-highlight .paradigm-name { color: var(--primary-light); }
.paradigm-full { font-size: 0.8rem; color: var(--text-muted); margin-bottom: 16px; }
.paradigm-question { font-style: italic; color: var(--text-muted); font-size: 0.9rem; margin-bottom: 12px; }
.paradigm-artifact { font-size: 0.85rem; }

.key-insight {
    max-width: 700px;
    margin: 0 auto;
}

.key-insight blockquote {
    padding: 24px 32px;
    border-left: 3px solid var(--primary);
    background: var(--primary-glow);
    border-radius: 0 var(--radius) var(--radius) 0;
    font-size: 1.05rem;
    color: var(--text);
    line-height: 1.8;
}

/* === Problem Grid === */
.problem-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 32px; max-width: 900px; margin: 0 auto; }

.problem-card {
    background: var(--surface);
    border-radius: var(--radius-lg);
    padding: 40px 32px;
    border: 1px solid var(--border);
}

.problem-card h3 { font-size: 1.3rem; margin-bottom: 24px; font-weight: 700; }

.problem-card ul { list-style: none; }
.problem-card li { padding: 8px 0; font-size: 0.95rem; display: flex; align-items: flex-start; gap: 10px; }

.icon-x { color: var(--red); font-weight: 700; flex-shrink: 0; }
.icon-check { color: var(--green); font-weight: 700; flex-shrink: 0; }

.problem-result {
    margin-top: 24px;
    padding: 16px;
    border-radius: var(--radius);
    background: rgba(239, 68, 68, 0.1);
    border: 1px solid rgba(239, 68, 68, 0.2);
    color: var(--red);
    text-align: center;
    font-weight: 600;
    font-style: italic;
}

.problem-result-good {
    background: rgba(34, 197, 94, 0.1) !important;
    border-color: rgba(34, 197, 94, 0.2) !important;
    color: var(--green) !important;
}

/* === Principles === */
.principles-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 24px; }

.principle-card {
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    padding: 36px 28px;
    transition: all 0.3s;
}
.principle-card:hover { border-color: var(--primary); transform: translateY(-4px); }

.principle-number {
    font-size: 2.5rem;
    font-weight: 900;
    background: var(--gradient);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    margin-bottom: 12px;
}

.principle-card h3 { font-size: 1.2rem; margin-bottom: 12px; font-weight: 700; }
.principle-card p { color: var(--text-muted); font-size: 0.95rem; }

/* === Spec Demo === */
.spec-demo { display: grid; grid-template-columns: 1.5fr 1fr; gap: 40px; align-items: start; }

.spec-window {
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    overflow: hidden;
}

.spec-titlebar {
    display: flex;
    align-items: center;
    gap: 12px;
    padding: 12px 16px;
    background: var(--bg);
    border-bottom: 1px solid var(--border);
}

.spec-dots { display: flex; gap: 6px; }
.dot { width: 12px; height: 12px; border-radius: 50%; }
.dot.red { background: var(--red); }
.dot.yellow { background: var(--yellow); }
.dot.green { background: var(--green); }
.spec-filename { color: var(--text-muted); font-size: 0.8rem; font-family: 'JetBrains Mono', monospace; }

.spec-code {
    padding: 24px;
    font-family: 'JetBrains Mono', monospace;
    font-size: 0.82rem;
    line-height: 1.7;
    overflow-x: auto;
    color: var(--text-muted);
}

.code-heading { color: var(--primary-light); font-weight: 600; }
.code-list { color: var(--accent); }
.code-value { color: var(--green); }
.code-bold { color: var(--text); font-weight: 600; }

.spec-annotations { display: flex; flex-direction: column; gap: 24px; }

.annotation {
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    padding: 24px;
    transition: all 0.3s;
}
.annotation:hover { border-color: var(--primary); }
.annotation-icon { font-size: 1.5rem; margin-bottom: 8px; }
.annotation h4 { font-size: 1rem; margin-bottom: 8px; }
.annotation p { color: var(--text-muted); font-size: 0.9rem; }

/* === Skills === */
.skills-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 20px;
    margin-bottom: 48px;
}

.skill-card {
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    padding: 28px 24px;
    transition: all 0.3s;
}
.skill-card:hover { border-color: var(--primary); transform: translateY(-4px); }
.skill-icon { font-size: 1.8rem; margin-bottom: 12px; }
.skill-card h3 { font-size: 1.1rem; margin-bottom: 8px; }
.skill-card p { color: var(--text-muted); font-size: 0.9rem; font-style: italic; }

.skills-portable {
    background: var(--primary-glow);
    border: 1px solid rgba(99, 102, 241, 0.2);
    border-radius: var(--radius-lg);
    padding: 40px;
    text-align: center;
}

.skills-portable h3 { font-size: 1.3rem; margin-bottom: 24px; }

.portable-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 16px;
    margin-bottom: 16px;
}

.portable-item {
    background: var(--surface);
    border-radius: var(--radius);
    padding: 16px;
}
.portable-item strong { display: block; color: var(--primary-light); margin-bottom: 4px; }
.portable-item span { font-size: 0.85rem; color: var(--text-muted); }
.portable-note { color: var(--text-muted); font-size: 0.9rem; }

/* === Workflow === */
.workflow-steps { max-width: 700px; margin: 0 auto; }

.workflow-step {
    display: flex;
    gap: 24px;
    padding: 32px 0;
    border-bottom: 1px solid var(--border);
    align-items: flex-start;
}
.workflow-step:last-child { border-bottom: none; }

.step-number {
    width: 48px; height: 48px;
    border-radius: 50%;
    background: var(--gradient);
    color: white;
    display: flex; align-items: center; justify-content: center;
    font-weight: 800;
    font-size: 1.2rem;
    flex-shrink: 0;
}

.step-content h3 { font-size: 1.2rem; margin-bottom: 8px; }
.step-content p { color: var(--text-muted); font-size: 0.95rem; }
.step-who { margin-top: 8px; font-size: 0.8rem; color: var(--primary-light); font-weight: 600; }

/* === Roles === */
.roles-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 24px; }

.role-card {
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: var(--radius-lg);
    padding: 40px 28px;
    text-align: center;
    transition: all 0.3s;
}
.role-card:hover { border-color: var(--primary); transform: translateY(-4px); }
.role-icon { font-size: 2.5rem; margin-bottom: 16px; }
.role-card h3 { margin-bottom: 8px; }
.role-does { color: var(--primary-light); font-weight: 600; margin-bottom: 12px; }
.role-card > p:last-child { color: var(--text-muted); font-size: 0.9rem; }

/* === Comparison Table === */
.comparison-table-wrapper { overflow-x: auto; margin-bottom: 48px; }

.comparison-table {
    width: 100%;
    border-collapse: collapse;
    background: var(--surface);
    border-radius: var(--radius);
    overflow: hidden;
}

.comparison-table th, .comparison-table td {
    padding: 16px 24px;
    text-align: left;
    border-bottom: 1px solid var(--border);
}

.comparison-table th {
    background: var(--bg);
    font-weight: 700;
    font-size: 0.9rem;
    text-transform: uppercase;
    letter-spacing: 0.03em;
}

.comparison-table td { font-size: 0.95rem; }
.comparison-table td:first-child { font-weight: 600; }
.highlight-col { color: var(--green); }
.comparison-table th.highlight-col { color: var(--primary-light); }

/* === Stats === */
.stats-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 24px; }

.stat-card {
    text-align: center;
    padding: 40px 24px;
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: var(--radius-lg);
}

.stat-number {
    font-size: 3.5rem;
    font-weight: 900;
    background: var(--gradient);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    line-height: 1;
    margin-bottom: 8px;
}

.stat-label { font-weight: 700; font-size: 1.1rem; margin-bottom: 8px; }
.stat-desc { color: var(--text-muted); font-size: 0.85rem; }

/* === Getting Started === */
.getting-started { max-width: 700px; margin: 0 auto; }

.gs-step {
    display: flex;
    gap: 20px;
    align-items: flex-start;
    padding: 24px 0;
    border-bottom: 1px solid var(--border);
}
.gs-step:last-child { border-bottom: none; }

.gs-number {
    width: 36px; height: 36px;
    border-radius: 50%;
    background: var(--surface);
    border: 1px solid var(--border);
    color: var(--primary-light);
    display: flex; align-items: center; justify-content: center;
    font-weight: 800;
    flex-shrink: 0;
}

.gs-code {
    font-family: 'JetBrains Mono', monospace;
    font-size: 0.85rem;
    color: var(--accent);
    background: var(--surface);
    padding: 6px 12px;
    border-radius: 6px;
    margin-bottom: 8px;
    display: inline-block;
}

.gs-step > div:last-child { display: flex; flex-direction: column; }
.gs-step p { color: var(--text-muted); font-size: 0.9rem; }

/* === Footer === */
.footer {
    padding: 80px 0 40px;
    border-top: 1px solid var(--border);
    background: var(--bg);
}

.footer-content {
    display: grid;
    grid-template-columns: 2fr 1fr 1fr 1fr;
    gap: 40px;
    margin-bottom: 48px;
}

.footer-logo { margin-bottom: 8px; }
.footer-logo-img { height: 48px; width: auto; }

.footer-brand p { color: var(--text-muted); font-size: 0.9rem; }
.footer-tagline { font-style: italic; }

.footer-links h4 { margin-bottom: 16px; font-size: 0.9rem; text-transform: uppercase; letter-spacing: 0.05em; }
.footer-links a {
    display: block;
    color: var(--text-muted);
    text-decoration: none;
    font-size: 0.9rem;
    padding: 4px 0;
    transition: color 0.2s;
}
.footer-links a:hover { color: var(--text); }

.footer-bottom {
    border-top: 1px solid var(--border);
    padding-top: 24px;
    text-align: center;
}

.footer-bottom p {
    color: var(--text-muted);
    font-style: italic;
    font-size: 0.9rem;
    max-width: 700px;
    margin: 0 auto;
}

/* ============================================
   RESPONSIVE — Desktop, Tablet, Mobile
   ============================================ */

/* --- Large Tablet / Small Desktop (≤1024px) --- */
@media (max-width: 1024px) {
    .container { padding: 0 20px; }

    .paradigm-grid { grid-template-columns: repeat(2, 1fr); }
    .principles-grid { grid-template-columns: repeat(2, 1fr); }
    .skills-grid { grid-template-columns: repeat(2, 1fr); }
    .roles-grid { grid-template-columns: repeat(3, 1fr); }
    .stats-grid { grid-template-columns: repeat(3, 1fr); }

    .spec-demo { grid-template-columns: 1fr; }
    .spec-annotations { flex-direction: row; gap: 16px; }
    .annotation { flex: 1; }

    .footer-content { grid-template-columns: 1fr 1fr; gap: 32px; }

    .section { padding: 100px 0; }
    .section-header { margin-bottom: 48px; }
}

/* --- Tablet Portrait (≤768px) --- */
@media (max-width: 768px) {
    /* Nav */
    .nav { padding: 14px 16px; flex-wrap: wrap; row-gap: 10px; }
    .nav-links { display: none; }
    .nav-toggle { display: block; margin-left: auto; }
    .nav-logo-img { height: 30px; }
    .lang-switcher { gap: 2px; padding: 2px; }
    .lang-btn { padding: 5px 7px; font-size: 0.65rem; }

    /* Hero */
    .hero { padding: 90px 16px 40px; min-height: auto; }
    .hero-badge { font-size: 0.78rem; padding: 5px 12px; margin-bottom: 16px; }
    .hero-subtitle { font-size: 1rem; margin-bottom: 28px; }
    .hero-ctas { flex-direction: column; align-items: center; gap: 12px; }
    .btn { padding: 12px 28px; font-size: 0.95rem; width: 100%; max-width: 280px; text-align: center; }
    .hero-visual { margin-top: 40px; }

    /* Flow diagram — grid on mobile */
    .flow-diagram {
        display: grid;
        grid-template-columns: repeat(3, 1fr);
        gap: 8px;
        padding: 20px 16px;
    }
    .flow-arrow { display: none; }
    .flow-step { min-width: unset; padding: 14px 8px; }
    .flow-icon { font-size: 1.6rem; }
    .flow-label { font-size: 0.78rem; }
    .flow-desc { font-size: 0.7rem; }

    /* Sections */
    .section { padding: 64px 0; }
    .section-header { margin-bottom: 36px; }
    .section-header h2 { margin-bottom: 12px; }
    .section-subtitle { font-size: 1rem; }
    .section-badge { font-size: 0.75rem; padding: 3px 12px; }

    /* Section Images */
    .section-image { margin: 0 auto 32px; border-radius: var(--radius); }

    /* Grids — 2 columns on tablet */
    .paradigm-grid { grid-template-columns: repeat(2, 1fr); gap: 12px; }
    .paradigm-card { padding: 24px 16px; }
    .paradigm-name { font-size: 1.5rem; }

    .problem-grid { grid-template-columns: 1fr; gap: 20px; }
    .problem-card { padding: 28px 20px; }

    .principles-grid { grid-template-columns: 1fr 1fr; gap: 16px; }
    .principle-card { padding: 28px 20px; }
    .principle-number { font-size: 2rem; }

    /* Spec demo */
    .spec-demo { grid-template-columns: 1fr; gap: 24px; }
    .spec-annotations { flex-direction: column; gap: 12px; }
    .spec-code { padding: 16px; font-size: 0.75rem; }

    /* Skills */
    .skills-grid { grid-template-columns: repeat(2, 1fr); gap: 12px; }
    .skill-card { padding: 20px 16px; }
    .portable-grid { grid-template-columns: repeat(2, 1fr); gap: 12px; }
    .skills-portable { padding: 28px 20px; }

    /* Workflow */
    .workflow-step { gap: 16px; padding: 24px 0; }
    .step-number { width: 40px; height: 40px; font-size: 1rem; }
    .step-content h3 { font-size: 1.05rem; }

    /* Roles */
    .roles-grid { grid-template-columns: 1fr; gap: 16px; }
    .role-card { padding: 28px 20px; }
    .role-icon { font-size: 2rem; }

    /* Comparison */
    .comparison-table th, .comparison-table td { padding: 12px 16px; font-size: 0.85rem; }

    /* Stats */
    .stats-grid { grid-template-columns: repeat(3, 1fr); gap: 12px; }
    .stat-card { padding: 28px 16px; }
    .stat-number { font-size: 2.5rem; }
    .stat-label { font-size: 0.95rem; }
    .stat-desc { font-size: 0.8rem; }

    /* Getting started */
    .gs-step { gap: 14px; padding: 18px 0; }
    .gs-code { font-size: 0.78rem; word-break: break-all; }

    /* Footer */
    .footer { padding: 48px 0 32px; }
    .footer-content { grid-template-columns: 1fr 1fr; gap: 28px; }
    .footer-logo-img { height: 40px; }

    /* Key insight */
    .key-insight blockquote { padding: 20px 24px; font-size: 0.95rem; }
}

/* --- Mobile (≤480px) --- */
@media (max-width: 480px) {
    .container { padding: 0 16px; }

    /* Nav */
    .nav { padding: 12px 16px; }
    .nav-logo-img { height: 26px; }

    /* Hero */
    .hero { padding: 80px 16px 32px; }
    .hero-badge { font-size: 0.72rem; }
    .hero-subtitle { font-size: 0.92rem; line-height: 1.7; }
    .btn { padding: 12px 24px; font-size: 0.9rem; }

    /* Flow diagram — 2 cols on small mobile */
    .flow-diagram { grid-template-columns: repeat(2, 1fr); gap: 6px; padding: 16px 12px; }
    .flow-step { padding: 12px 6px; }
    .flow-icon { font-size: 1.4rem; margin-bottom: 4px; }
    .flow-label { font-size: 0.72rem; }
    .flow-desc { font-size: 0.65rem; }

    /* Sections */
    .section { padding: 48px 0; }
    .section-header { margin-bottom: 28px; }

    /* Grids — 1 column */
    .paradigm-grid { grid-template-columns: 1fr; gap: 12px; }
    .principles-grid { grid-template-columns: 1fr; gap: 12px; }
    .skills-grid { grid-template-columns: 1fr; gap: 12px; }

    /* Spec demo */
    .spec-code { padding: 12px; font-size: 0.7rem; line-height: 1.6; }
    .annotation { padding: 16px; }
    .annotation-icon { font-size: 1.2rem; }
    .annotation h4 { font-size: 0.9rem; }
    .annotation p { font-size: 0.82rem; }

    /* Portable */
    .portable-grid { grid-template-columns: 1fr 1fr; gap: 8px; }
    .portable-item { padding: 12px; }
    .portable-item strong { font-size: 0.85rem; }
    .portable-item span { font-size: 0.78rem; }
    .skills-portable { padding: 20px 16px; }
    .skills-portable h3 { font-size: 1.1rem; }

    /* Workflow */
    .workflow-step { gap: 12px; padding: 20px 0; }
    .step-number { width: 36px; height: 36px; font-size: 0.9rem; }
    .step-content h3 { font-size: 1rem; }
    .step-content p { font-size: 0.88rem; }
    .step-who { font-size: 0.75rem; }

    /* Stats */
    .stats-grid { grid-template-columns: 1fr; gap: 12px; }
    .stat-card { padding: 24px 16px; }
    .stat-number { font-size: 2.2rem; }
    .stat-label { font-size: 0.9rem; }

    /* Comparison table — card view */
    .comparison-table th, .comparison-table td { padding: 10px 12px; font-size: 0.8rem; }
    .comparison-table th:first-child, .comparison-table td:first-child { min-width: 80px; }

    /* Getting started */
    .gs-step { flex-direction: column; gap: 8px; text-align: center; align-items: center; }
    .gs-code { font-size: 0.72rem; text-align: left; max-width: 100%; overflow-x: auto; }
    .gs-step > div:last-child { align-items: center; }

    /* Footer */
    .footer { padding: 36px 0 24px; }
    .footer-content { grid-template-columns: 1fr; gap: 24px; text-align: center; }
    .footer-brand { display: flex; flex-direction: column; align-items: center; }
    .footer-links { text-align: center; }
    .footer-logo-img { height: 36px; }
    .footer-bottom p { font-size: 0.82rem; }

    /* Key insight */
    .key-insight blockquote { padding: 16px 18px; font-size: 0.88rem; }

    /* Problem cards */
    .problem-card { padding: 24px 16px; }
    .problem-card h3 { font-size: 1.1rem; margin-bottom: 16px; }
    .problem-card li { font-size: 0.88rem; }
    .problem-result { font-size: 0.88rem; padding: 12px; }
}

/* --- Very small screens (≤360px) --- */
@media (max-width: 360px) {
    .container { padding: 0 12px; }
    .hero { padding: 76px 12px 24px; }
    .hero-subtitle { font-size: 0.85rem; }
    .flow-diagram { grid-template-columns: repeat(2, 1fr); padding: 12px 8px; }
    .spec-code { font-size: 0.65rem; padding: 10px; }
    .comparison-table th, .comparison-table td { padding: 8px 8px; font-size: 0.75rem; }
    .stat-number { font-size: 1.8rem; }
}

/* --- Landscape mobile --- */
@media (max-height: 500px) and (orientation: landscape) {
    .hero { min-height: auto; padding: 80px 24px 32px; }
    .hero-visual { margin-top: 24px; }
    .flow-diagram { padding: 16px; }
}

/* --- Touch device optimizations --- */
@media (hover: none) and (pointer: coarse) {
    .flow-step:hover,
    .paradigm-card:hover,
    .principle-card:hover,
    .skill-card:hover,
    .role-card:hover,
    .annotation:hover,
    .section-image:hover img {
        transform: none;
    }
    .btn-primary:hover { transform: none; box-shadow: none; }
}