/* ==========================================================================
   Attestra — Dark Theme Landing Page
   Palette: Navy #0d131c + Blue accent #1D4ED8
   Fonts: Space Grotesk (display), Inter (body), JetBrains Mono (code)
   Pattern: AgentBuilders.app code-level quality
   ========================================================================== */

@import url('https://fonts.googleapis.com/css2?family=Inter:wght@400;500;600;700&family=Space+Grotesk:wght@500;600;700&family=JetBrains+Mono:wght@400&display=swap');

*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

:root {
  --bg: #0d131c;
  --bg-surface: rgba(255, 255, 255, 0.03);
  --bg-elevated: rgba(255, 255, 255, 0.05);
  --accent: #3B82F6;
  --accent-dark: #1D4ED8;
  --accent-glow: rgba(59, 130, 246, 0.25);
  --accent-subtle: rgba(59, 130, 246, 0.12);
  --text: #e8eaed;
  --text-secondary: rgba(232, 234, 237, 0.72);
  --text-tertiary: rgba(232, 234, 237, 0.40);
  --border: rgba(255, 255, 255, 0.06);
  --border-hover: rgba(59, 130, 246, 0.30);
  --border-medium: rgba(255, 255, 255, 0.12);
  --success: #34d399;
  --error: #f87171;
  --error-bg: rgba(248, 113, 113, 0.10);
  --font-display: 'Space Grotesk', -apple-system, sans-serif;
  --font-body: 'Inter', -apple-system, sans-serif;
  --font-mono: 'JetBrains Mono', 'SF Mono', monospace;
  --radius: 12px;
  --radius-sm: 8px;
  --container: 1120px;
  --padding: clamp(1.25rem, 1rem + 1.5vw, 3rem);
  --ease: cubic-bezier(0.16, 1, 0.3, 1);
}

html { font-size: 16px; scroll-behavior: smooth; -webkit-font-smoothing: antialiased; }
body { font-family: var(--font-body); color: var(--text); background: var(--bg); line-height: 1.6; }
img, svg { display: block; max-width: 100%; }
a { color: var(--accent); text-decoration: none; transition: color 0.15s ease; }
a:hover { color: #60a5fa; }

/* ── Skip Link ── */
.skip-link { position: absolute; top: -100%; left: 1rem; background: var(--accent-dark); color: #fff; padding: 0.5rem 1rem; border-radius: var(--radius-sm); font-size: 0.875rem; z-index: 200; }
.skip-link:focus { top: 0.5rem; }

/* ── Container ── */
.container { max-width: var(--container); margin: 0 auto; padding-left: var(--padding); padding-right: var(--padding); }

/* ── Nav ── */
.site-nav { position: sticky; top: 0; z-index: 100; background: rgba(13, 19, 28, 0.92); backdrop-filter: blur(8px); -webkit-backdrop-filter: blur(8px); border-bottom: 1px solid var(--border); }
.nav-inner { display: flex; align-items: center; justify-content: space-between; height: 56px; }
.nav-brand { font-family: var(--font-display); font-size: 1.0625rem; font-weight: 600; color: var(--text); letter-spacing: -0.02em; display: flex; align-items: center; gap: 8px; }
.nav-brand svg { width: 24px; height: auto; }
.nav-links { display: flex; align-items: center; gap: 2rem; list-style: none; }
.nav-links a { font-size: 0.875rem; font-weight: 500; color: var(--text-secondary); transition: color 0.15s ease; }
.nav-links a:hover { color: var(--text); text-decoration: none; }

/* ── Buttons ── */
.btn { display: inline-flex; align-items: center; justify-content: center; font-family: var(--font-body); font-weight: 600; border-radius: var(--radius-sm); border: none; cursor: pointer; transition: background 0.15s ease, transform 0.1s ease, box-shadow 0.15s ease; text-decoration: none; }
.btn--sm { padding: 8px 18px; font-size: 0.8125rem; }
.btn--md { padding: 10px 22px; font-size: 0.875rem; }
.btn--lg { padding: 14px 28px; font-size: 0.9375rem; }
.btn--primary { background: var(--accent-dark); color: #fff; box-shadow: 0 1px 3px rgba(29, 78, 216, 0.4); }
.btn--primary:hover { background: var(--accent); color: #fff; text-decoration: none; }
.btn--primary:active { transform: translateY(1px); box-shadow: none; }
.btn--secondary { background: transparent; color: var(--text-secondary); border: 1px solid rgba(255, 255, 255, 0.15); }
.btn--secondary:hover { color: var(--text); border-color: rgba(255, 255, 255, 0.35); background: rgba(255, 255, 255, 0.04); text-decoration: none; }
.btn--secondary:active { transform: translateY(1px); }
.btn--success { background: #16a34a; color: #fff; box-shadow: 0 1px 3px rgba(22, 163, 74, 0.4); }
.btn:focus-visible { outline: 2px solid var(--accent); outline-offset: 2px; }

/* Mobile nav */
.nav-toggle { display: none; }
.nav-toggle-label { display: none; cursor: pointer; width: 24px; height: 24px; position: relative; }
.nav-toggle-label span, .nav-toggle-label span::before, .nav-toggle-label span::after { display: block; width: 18px; height: 1.5px; background: var(--text); position: absolute; transition: transform 0.15s ease; }
.nav-toggle-label span { top: 50%; left: 3px; transform: translateY(-50%); }
.nav-toggle-label span::before { content: ""; top: -6px; }
.nav-toggle-label span::after { content: ""; top: 6px; }

/* ── Scroll Reveal ── */
[data-motion] { opacity: 0; transform: translateY(20px); transition: opacity 0.6s var(--ease), transform 0.6s var(--ease); }
[data-motion].revealed { opacity: 1; transform: translateY(0); }

/* ── Hero ── */
.hero { padding: 7rem 0 5rem; text-align: center; }
.hero-label { display: inline-block; font-size: 0.75rem; font-weight: 600; letter-spacing: 0.06em; text-transform: uppercase; color: var(--accent); background: var(--accent-subtle); border: 1px solid rgba(59, 130, 246, 0.20); padding: 0.3rem 0.85rem; border-radius: 9999px; margin-bottom: 1.5rem; }
.hero h1 { font-family: var(--font-display); font-size: clamp(2.25rem, 1.8rem + 2.5vw, 3.5rem); font-weight: 700; line-height: 1.1; letter-spacing: -0.035em; max-width: 820px; margin: 0 auto 1.5rem; }
.hero .text-gradient { background: linear-gradient(135deg, var(--text) 0%, var(--accent) 50%, #60a5fa 100%); -webkit-background-clip: text; -webkit-text-fill-color: transparent; background-clip: text; }
.hero-subtitle { font-size: clamp(1rem, 0.95rem + 0.25vw, 1.125rem); color: var(--text-secondary); line-height: 1.7; max-width: 580px; margin: 0 auto 2rem; }
.hero-actions { display: flex; align-items: center; justify-content: center; gap: 1rem; flex-wrap: wrap; }

/* ── Code Demo Window ── */
.demo { max-width: 680px; margin: 3rem auto 0; }
.demo-window { background: rgba(0, 0, 0, 0.45); border: 1px solid var(--border); border-radius: var(--radius); overflow: hidden; }
.demo-titlebar { display: flex; align-items: center; gap: 6px; padding: 12px 16px; border-bottom: 1px solid var(--border); }
.demo-dot { width: 10px; height: 10px; border-radius: 50%; }
.demo-dot--red { background: #ff5f57; }
.demo-dot--yellow { background: #ffbd2e; }
.demo-dot--green { background: #28c840; }
.demo-title { margin-left: 8px; font-size: 0.75rem; color: var(--text-tertiary); font-family: var(--font-mono); }
.demo-body { padding: 20px 24px; font-family: var(--font-mono); font-size: 0.8125rem; line-height: 1.8; color: var(--text-secondary); overflow-x: auto; }
.demo-body .cmd { color: var(--text-tertiary); }
.demo-body .highlight { color: var(--accent); }
.demo-body .success { color: var(--success); }
.demo-body .dim { color: var(--text-tertiary); }
.demo-body .score { color: #fbbf24; font-weight: 600; }
.demo-body .finding { color: var(--error); }

/* ── Section ── */
.section { padding: 5rem 0; }
.section--alt { background: rgba(255, 255, 255, 0.015); }
.section-header { text-align: center; margin-bottom: 3rem; }
.section-header h2 { font-family: var(--font-display); font-size: clamp(1.5rem, 1.2rem + 1.5vw, 2.25rem); font-weight: 700; line-height: 1.15; letter-spacing: -0.03em; margin-bottom: 1rem; }
.section-header p { font-size: 1rem; color: var(--text-secondary); max-width: 560px; margin: 0 auto; line-height: 1.7; }

/* ── Problem ── */
.problem-grid { display: grid; grid-template-columns: repeat(2, 1fr); gap: 1rem; max-width: 880px; margin: 0 auto; }
.problem-item { background: var(--bg-surface); border: 1px solid var(--border); border-radius: var(--radius); padding: 1.5rem; transition: border-color 0.2s ease; }
.problem-item:hover { border-color: var(--border-medium); }
.problem-item h3 { font-family: var(--font-display); font-size: 0.9375rem; font-weight: 600; margin-bottom: 0.5rem; }
.problem-item p { font-size: 0.875rem; color: var(--text-secondary); line-height: 1.65; }

/* ── Works With ── */
.works-with { padding: 3rem 0; text-align: center; border-top: 1px solid var(--border); border-bottom: 1px solid var(--border); }
.works-with-label { font-size: 0.6875rem; font-weight: 600; letter-spacing: 0.08em; text-transform: uppercase; color: var(--text-tertiary); margin-bottom: 1.5rem; }
.works-with-logos { display: flex; align-items: center; justify-content: center; gap: 2.5rem; flex-wrap: wrap; opacity: 0.4; }
.works-with-logos span { font-family: var(--font-display); font-size: 0.9375rem; font-weight: 600; color: var(--text); }

/* ── Features ── */
.features-grid { display: grid; grid-template-columns: repeat(2, 1fr); gap: 1rem; }
.feature-card { background: var(--bg-surface); border: 1px solid var(--border); border-radius: var(--radius); padding: 1.75rem; transition: border-color 0.2s ease, transform 0.2s ease; }
.feature-card:hover { border-color: var(--border-hover); transform: translateY(-2px); }
.feature-icon { width: 40px; height: 40px; display: flex; align-items: center; justify-content: center; background: var(--accent-subtle); border-radius: 10px; margin-bottom: 1rem; color: var(--accent); }
.feature-icon svg { width: 20px; height: 20px; }
.feature-card h3 { font-family: var(--font-display); font-size: 1rem; font-weight: 600; margin-bottom: 0.5rem; }
.feature-card p { font-size: 0.875rem; color: var(--text-secondary); line-height: 1.65; }

/* ── Observability ── */
.obs-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 1rem; }
.obs-card { background: var(--bg-surface); border: 1px solid var(--border); border-radius: var(--radius); padding: 1.5rem; text-align: center; transition: border-color 0.2s ease; }
.obs-card:hover { border-color: var(--border-hover); }
.obs-badge { display: inline-block; padding: 0.2rem 0.6rem; border-radius: 9999px; font-size: 0.6875rem; font-weight: 600; text-transform: uppercase; letter-spacing: 0.04em; margin-bottom: 1rem; }
.obs-badge--blue { background: rgba(59, 130, 246, 0.15); color: #60a5fa; border: 1px solid rgba(59, 130, 246, 0.3); }
.obs-badge--green { background: rgba(52, 211, 153, 0.15); color: #34d399; border: 1px solid rgba(52, 211, 153, 0.3); }
.obs-badge--amber { background: rgba(251, 191, 36, 0.15); color: #fbbf24; border: 1px solid rgba(251, 191, 36, 0.3); }
.obs-card h3 { font-family: var(--font-display); font-size: 0.9375rem; font-weight: 600; margin-bottom: 0.5rem; }
.obs-card p { font-size: 0.8125rem; color: var(--text-secondary); line-height: 1.6; }
.obs-callout { max-width: 640px; margin: 2.5rem auto 0; text-align: center; padding: 1.5rem 2rem; background: var(--bg-surface); border: 1px solid var(--border-hover); border-radius: var(--radius); }
.obs-callout p { font-size: 0.9375rem; color: var(--text-secondary); line-height: 1.6; }
.obs-callout strong { color: var(--text); }

/* ── Approach Grid (S3) ── */
.approach-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 1rem; }
.approach-step { background: var(--bg-surface); border: 1px solid var(--border); border-radius: var(--radius); padding: 1.5rem; transition: border-color 0.2s ease; }
.approach-step:hover { border-color: var(--border-hover); }
.approach-icon { width: 40px; height: 40px; display: flex; align-items: center; justify-content: center; background: var(--accent-subtle); border-radius: 10px; margin-bottom: 1rem; color: var(--accent); }
.approach-icon--accent { background: rgba(59, 130, 246, 0.20); border: 1px solid rgba(59, 130, 246, 0.30); }
.approach-icon svg { width: 20px; height: 20px; }
.approach-step h3 { font-family: var(--font-display); font-size: 1rem; font-weight: 600; margin-bottom: 0.5rem; }
.approach-step p { font-size: 0.8125rem; color: var(--text-secondary); line-height: 1.65; }
.approach-contrast { display: block; margin-top: 0.75rem; font-size: 0.75rem; color: var(--accent); font-weight: 500; line-height: 1.5; }
.hunter-list { list-style: none; margin: 0.625rem 0 0.5rem; }
.hunter-list li { font-size: 0.8125rem; color: var(--text-secondary); padding: 0.25rem 0 0.25rem 1rem; position: relative; line-height: 1.5; }
.hunter-list li::before { content: ""; position: absolute; left: 0; top: 0.55rem; width: 5px; height: 5px; border-radius: 50%; background: var(--accent); }
.hunter-list li strong { color: var(--text); }
.hunter-note { font-size: 0.6875rem; color: var(--text-tertiary); margin-top: 0.375rem; line-height: 1.5; }
.section-cta { text-align: center; margin-top: 2.5rem; }

/* ── Split Grid (S4: Fixes + EA) ── */
.split-grid { display: grid; grid-template-columns: repeat(2, 1fr); gap: 1rem; }
.split-card { background: var(--bg-surface); border: 1px solid var(--border); border-radius: var(--radius); padding: 1.75rem; }
.split-card:hover { border-color: var(--border-hover); }
.card-label { display: inline-block; font-size: 0.6875rem; font-weight: 600; letter-spacing: 0.06em; text-transform: uppercase; padding: 0.2rem 0.6rem; border-radius: 9999px; margin-bottom: 1rem; }
.card-label--blue { background: rgba(59, 130, 246, 0.15); color: #60a5fa; border: 1px solid rgba(59, 130, 246, 0.3); }
.card-label--green { background: rgba(52, 211, 153, 0.15); color: #34d399; border: 1px solid rgba(52, 211, 153, 0.3); }
.split-card h3 { font-family: var(--font-display); font-size: 1.125rem; font-weight: 600; margin-bottom: 0.5rem; }
.split-card p { font-size: 0.875rem; color: var(--text-secondary); line-height: 1.65; margin-bottom: 1rem; }
.feature-list { list-style: none; }
.feature-list li { font-size: 0.8125rem; color: var(--text-secondary); padding: 0.375rem 0; padding-left: 1.25rem; position: relative; line-height: 1.55; }
.feature-list li::before { content: ""; position: absolute; left: 0; top: 0.6rem; width: 6px; height: 6px; border-radius: 50%; background: var(--accent); }

/* ── Score Visual (S5) ── */
.score-grid { display: grid; grid-template-columns: 1.4fr 1fr; gap: 2.5rem; align-items: center; max-width: 800px; margin: 0 auto; }
.score-dimensions { display: flex; flex-direction: column; gap: 1rem; }
.score-dim-header { display: flex; justify-content: space-between; font-size: 0.8125rem; color: var(--text-secondary); margin-bottom: 0.375rem; }
.score-dim-weight { color: var(--text-tertiary); font-family: var(--font-mono); font-size: 0.75rem; }
.score-bar { height: 8px; background: rgba(255, 255, 255, 0.06); border-radius: 4px; overflow: hidden; }
.score-bar-fill { height: 100%; background: var(--accent); border-radius: 4px; transition: width 0.6s var(--ease); }
.score-bar-fill--warn { background: #fbbf24; }
.score-info { text-align: center; }
.score-big { font-family: var(--font-display); font-size: 4rem; font-weight: 700; letter-spacing: -0.04em; line-height: 1; }
.score-big span { font-size: 1.5rem; color: var(--text-tertiary); font-weight: 400; }
.score-grade { font-size: 0.875rem; color: var(--text-secondary); margin-top: 0.5rem; }
.score-detail { font-size: 0.8125rem; color: var(--text-tertiary); margin-top: 1rem; line-height: 1.6; }
.score-improve { font-size: 0.875rem; color: var(--accent); margin-top: 1rem; }

/* ── Agent Grid (S6) ── */
.agent-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 1rem; }
.agent-card { background: var(--bg-surface); border: 1px solid var(--border); border-radius: var(--radius); padding: 1.5rem; transition: border-color 0.2s ease; }
.agent-card:hover { border-color: var(--border-hover); }
.agent-card h3 { font-family: var(--font-display); font-size: 0.9375rem; font-weight: 600; margin-bottom: 0.5rem; }
.agent-card p { font-size: 0.8125rem; color: var(--text-secondary); line-height: 1.6; }
.privacy-callout { display: flex; align-items: flex-start; gap: 0.75rem; max-width: 560px; margin: 2rem auto 0; padding: 1rem 1.5rem; background: var(--bg-surface); border: 1px solid var(--border); border-radius: var(--radius-sm); }
.privacy-callout svg { flex-shrink: 0; color: var(--accent); margin-top: 2px; }
.privacy-callout p { font-size: 0.8125rem; color: var(--text-secondary); line-height: 1.6; }

/* ── Comparison Table (S7) ── */
.compare-table-wrap { overflow-x: auto; -webkit-overflow-scrolling: touch; }
.compare-table { width: 100%; border-collapse: collapse; font-size: 0.8125rem; }
.compare-table th { text-align: left; font-weight: 600; color: var(--text-tertiary); font-size: 0.75rem; text-transform: uppercase; letter-spacing: 0.05em; padding: 0.75rem 1rem; border-bottom: 1px solid var(--border-medium); white-space: nowrap; }
.compare-table td { padding: 0.75rem 1rem; color: var(--text-secondary); border-bottom: 1px solid var(--border); vertical-align: middle; }
.compare-table tbody tr:hover { background: rgba(59, 130, 246, 0.04); }
.compare-highlight { color: var(--accent) !important; }
.compare-yes { color: var(--success); font-weight: 600; }
.compare-no { color: var(--text-tertiary); }
.compare-partial { color: #fbbf24; }

/* ── Founder Tiers (S8) ── */
.founder-benefits { font-size: 0.8125rem; color: var(--text-secondary); margin-bottom: 0.5rem; line-height: 1.6; }

/* ── Steps ── */
.steps { display: grid; grid-template-columns: repeat(3, 1fr); gap: 1.5rem; position: relative; }
.steps::before { content: ""; position: absolute; top: 24px; left: calc(100% / 6); right: calc(100% / 6); height: 1px; background: var(--border-medium); }
.step { text-align: center; position: relative; }
.step-number { display: inline-flex; align-items: center; justify-content: center; width: 48px; height: 48px; background: var(--bg); border: 1px solid var(--border-medium); border-radius: 50%; font-family: var(--font-display); font-size: 1rem; font-weight: 600; color: var(--accent); margin-bottom: 1rem; position: relative; z-index: 1; }
.step h3 { font-family: var(--font-display); font-size: 1rem; font-weight: 600; margin-bottom: 0.5rem; }
.step p { font-size: 0.875rem; color: var(--text-secondary); line-height: 1.65; max-width: 300px; margin: 0 auto; }

/* ── Pricing Teaser ── */
.founder { background: var(--bg-surface); border: 1px solid var(--border-hover); border-radius: var(--radius); padding: 2rem 2.5rem; text-align: center; max-width: 640px; margin: 0 auto; }
.founder h3 { font-family: var(--font-display); font-size: 1.25rem; font-weight: 700; margin-bottom: 0.5rem; letter-spacing: -0.01em; }
.founder > p { font-size: 0.9375rem; color: var(--text-secondary); margin-bottom: 1.5rem; line-height: 1.65; }

/* ── Waitlist Form ── */
.waitlist { padding: 6rem 0; text-align: center; }
.waitlist h2 { font-family: var(--font-display); font-size: clamp(1.5rem, 1.2rem + 1.5vw, 2.25rem); font-weight: 700; line-height: 1.15; letter-spacing: -0.03em; margin-bottom: 0.75rem; }
.waitlist > .container > p { font-size: 1rem; color: var(--text-secondary); margin-bottom: 2rem; }
.waitlist-form { display: flex; align-items: flex-start; justify-content: center; gap: 0.75rem; max-width: 440px; margin: 0 auto; }
.waitlist-form .form-group { flex: 1; text-align: left; }
.form-input { width: 100%; padding: 0.625rem 0.75rem; font-family: var(--font-body); font-size: 0.9375rem; color: var(--text); background: rgba(255, 255, 255, 0.05); border: 1px solid rgba(255, 255, 255, 0.10); border-radius: var(--radius-sm); transition: border-color 0.15s ease, box-shadow 0.15s ease; }
.form-input::placeholder { color: var(--text-tertiary); }
.form-input:focus { border-color: var(--accent-dark); box-shadow: 0 0 0 3px var(--accent-glow); outline: none; }
.form-input[aria-invalid="true"] { border-color: var(--error); box-shadow: 0 0 0 3px var(--error-bg); }
.form-error { display: none; font-size: 0.75rem; color: var(--error); margin-top: 0.375rem; }
.form-error.visible { display: block; }
.waitlist-success { display: none; text-align: center; }
.waitlist-success.visible { display: block; }
.waitlist-success .checkmark { width: 56px; height: 56px; border-radius: 50%; background: #16a34a; display: flex; align-items: center; justify-content: center; margin: 0 auto 1rem; }
.waitlist-success .checkmark::after { content: ""; display: block; width: 14px; height: 24px; border: solid #fff; border-width: 0 3px 3px 0; transform: rotate(45deg) translateY(-2px); }
.waitlist-success p { font-size: 1.0625rem; color: var(--text); font-weight: 500; }
.waitlist-success .sub { font-size: 0.875rem; color: var(--text-secondary); font-weight: 400; margin-top: 0.25rem; }

/* Spinner */
.spinner { display: inline-block; width: 14px; height: 14px; border: 2px solid rgba(255, 255, 255, 0.3); border-top-color: #fff; border-radius: 50%; animation: spin 0.6s linear infinite; margin-right: 6px; }
@keyframes spin { to { transform: rotate(360deg); } }

/* ── Footer ── */
.site-footer { border-top: 1px solid var(--border); padding: 4rem 0 2rem; }
.footer-inner { display: grid; grid-template-columns: 2fr 1fr 1fr 1fr; gap: 3rem; margin-bottom: 3rem; }
.footer-brand { font-family: var(--font-display); font-weight: 600; }
.footer-brand p { font-family: var(--font-body); font-size: 0.875rem; font-weight: 400; color: var(--text-secondary); margin-top: 0.5rem; line-height: 1.6; max-width: 260px; }
.footer-col h4 { font-size: 0.6875rem; font-weight: 600; letter-spacing: 0.08em; text-transform: uppercase; color: var(--text-tertiary); margin-bottom: 1rem; }
.footer-col ul { list-style: none; }
.footer-col li { margin-bottom: 0.5rem; }
.footer-col a { font-size: 0.875rem; color: var(--text-secondary); transition: color 0.15s ease; }
.footer-col a:hover { color: var(--text); text-decoration: none; }
.footer-bottom { border-top: 1px solid var(--border); padding-top: 1.5rem; font-size: 0.8125rem; color: var(--text-tertiary); }

/* ── Focus ── */
*:focus-visible { outline: 2px solid var(--accent); outline-offset: 2px; }
*:focus:not(:focus-visible) { outline: none; }
.sr-only { position: absolute; width: 1px; height: 1px; padding: 0; margin: -1px; overflow: hidden; clip: rect(0,0,0,0); white-space: nowrap; border: 0; }

/* ── Reduced Motion ── */
@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after { animation-duration: 0.01ms !important; transition-duration: 0.01ms !important; }
  html { scroll-behavior: auto; }
  [data-motion] { opacity: 1; transform: none; }
}

/* ── Tablet ── */
@media (max-width: 1023px) {
  .approach-grid { grid-template-columns: repeat(2, 1fr); }
  .split-grid { grid-template-columns: 1fr; }
  .score-grid { grid-template-columns: 1fr; max-width: 480px; margin: 0 auto; }
  .score-info { text-align: center; }
  .agent-grid { grid-template-columns: 1fr; max-width: 480px; margin-left: auto; margin-right: auto; }
  .obs-grid { grid-template-columns: 1fr; max-width: 400px; margin-left: auto; margin-right: auto; }
  .steps { grid-template-columns: 1fr; gap: 1.5rem; }
  .steps::before { display: none; }
  .footer-inner { grid-template-columns: 1fr 1fr; gap: 2rem; }
  .footer-brand { grid-column: 1 / -1; }
}

/* ── Mobile ── */
@media (max-width: 639px) {
  .hero { padding: 4rem 0 3rem; }
  .approach-grid { grid-template-columns: 1fr; }
  .problem-grid { grid-template-columns: 1fr; }
  .features-grid { grid-template-columns: 1fr; }
  .compare-table { font-size: 0.75rem; }
  .compare-table th, .compare-table td { padding: 0.5rem 0.625rem; }
  .waitlist-form { flex-direction: column; }
  .waitlist-form .btn { width: 100%; }
  .footer-inner { grid-template-columns: 1fr; gap: 1.5rem; }
  .nav-toggle-label { display: block; }
  .nav-links { position: absolute; top: 56px; left: 0; right: 0; flex-direction: column; background: rgba(13, 19, 28, 0.95); backdrop-filter: blur(12px); -webkit-backdrop-filter: blur(12px); border-bottom: 1px solid var(--border); padding: 1rem var(--padding); gap: 1rem; display: none; }
  .nav-toggle:checked ~ .nav-links { display: flex; }
}