/* ==========================================================================
   SafeVault for Mac — Marketing page stylesheet
   重写于第二轮：营销叙事 + 极简技术提及。
   颜色 / 字体可整组替换为你的品牌规范。
   ========================================================================== */

:root {
  --ink:           #0a0e1a;
  --ink-soft:      #3d4453;
  --muted:         #7b8290;
  --line:          #e6e8ee;
  --line-soft:     #eef0f4;
  --bg:            #ffffff;
  --bg-alt:        #f7f8fb;
  --bg-tint:       #eef1ff;
  --bg-dark:       #0a0e1a;
  --accent:        #2545e8;
  --accent-dark:   #1a32b8;
  --accent-soft:   #eef1ff;
  --success:       #0f8a4a;
  --warn:          #b76a00;
  --danger:        #c0392b;

  --radius:        12px;
  --radius-sm:     8px;
  --radius-lg:     18px;

  --shadow-sm:     0 1px 2px rgba(10, 14, 26, 0.05),
                   0 1px 3px rgba(10, 14, 26, 0.06);
  --shadow-md:     0 8px 24px -8px rgba(10, 14, 26, 0.12);
  --shadow-lg:     0 40px 80px -24px rgba(10, 14, 26, 0.35);

  --font-sans:     -apple-system, BlinkMacSystemFont, "SF Pro Display",
                   "SF Pro Text", "Inter", "Helvetica Neue", Arial, sans-serif;
  --font-mono:     ui-monospace, "SF Mono", Menlo, Consolas, monospace;

  --max:           1120px;
  --max-narrow:    760px;
}

* { box-sizing: border-box; }
html, body { margin: 0; padding: 0; }

body {
  font-family: var(--font-sans);
  font-size: 17px;
  line-height: 1.6;
  color: var(--ink);
  background: var(--bg);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

a { color: var(--accent); text-decoration: none; }
a:hover { text-decoration: underline; }

img, svg { max-width: 100%; display: block; }

.container {
  max-width: var(--max);
  margin: 0 auto;
  padding: 0 24px;
}
.container.narrow { max-width: var(--max-narrow); }

.visually-hidden {
  position: absolute;
  width: 1px; height: 1px;
  padding: 0; margin: -1px;
  overflow: hidden; clip: rect(0,0,0,0);
  white-space: nowrap; border: 0;
}

.center { text-align: center; }
.muted  { color: var(--muted); }

/* ==========================================================================
   Typography helpers
   ========================================================================== */
.eyebrow {
  display: inline-block;
  font-size: 12px;
  font-weight: 600;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--accent);
  margin: 0 0 16px;
}
.eyebrow.center { display: block; }

h1, h2, h3 {
  letter-spacing: -0.02em;
  font-weight: 600;
  color: var(--ink);
  margin: 0 0 16px;
}

.lede {
  font-size: 19px;
  line-height: 1.6;
  color: var(--ink-soft);
  margin: 0 0 18px;
  max-width: 640px;
}

/* ==========================================================================
   Buttons
   ========================================================================== */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 10px 18px;
  border-radius: var(--radius-sm);
  font-size: 15px;
  font-weight: 600;
  border: 1px solid transparent;
  cursor: pointer;
  transition: background .15s, color .15s, border-color .15s, transform .15s;
  text-decoration: none !important;
  white-space: nowrap;
}
.btn.lg { padding: 14px 26px; font-size: 16px; border-radius: 10px; }
.btn.primary { background: var(--accent); color: #fff; }
.btn.primary:hover { background: var(--accent-dark); }
.btn.ghost {
  background: transparent;
  color: var(--ink);
  border-color: var(--line);
}
.btn.ghost:hover { border-color: var(--ink); background: var(--bg-alt); }

/* ==========================================================================
   Header
   ========================================================================== */
.site-header {
  position: sticky;
  top: 0;
  background: rgba(255, 255, 255, 0.85);
  backdrop-filter: saturate(180%) blur(14px);
  border-bottom: 1px solid var(--line);
  z-index: 50;
}

.nav-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
  padding: 14px 24px;
}

.brand {
  display: flex;
  align-items: center;
  gap: 10px;
  color: var(--ink);
  font-weight: 600;
  font-size: 17px;
}
.brand:hover { text-decoration: none; }
.brand-mark { width: 22px; height: 22px; color: var(--accent); }
.brand-name { letter-spacing: -0.01em; }

.nav-links {
  list-style: none;
  display: flex;
  gap: 28px;
  margin: 0;
  padding: 0;
}
.nav-links a {
  color: var(--ink-soft);
  font-size: 14.5px;
  font-weight: 500;
}
.nav-links a:hover { color: var(--accent); text-decoration: none; }

/* ==========================================================================
   Hero
   ========================================================================== */
.hero {
  padding: 88px 0 64px;
  background:
    radial-gradient(900px 360px at 20% -10%, rgba(37, 69, 232, 0.10), transparent 60%),
    radial-gradient(700px 320px at 100% 0%, rgba(37, 69, 232, 0.06), transparent 60%),
    var(--bg);
  overflow: hidden;
}

.hero-inner { text-align: center; }

.hero-title {
  font-size: clamp(38px, 6.4vw, 68px);
  line-height: 1.05;
  margin: 0 auto 22px;
  max-width: 880px;
  letter-spacing: -0.03em;
}
.hero-title-em {
  background: linear-gradient(180deg, var(--accent) 0%, var(--accent-dark) 100%);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
  font-style: italic;
}

.hero-lede {
  font-size: 19px;
  color: var(--ink-soft);
  max-width: 620px;
  margin: 0 auto 32px;
  line-height: 1.6;
}

.cta-row {
  display: flex;
  gap: 12px;
  justify-content: center;
  flex-wrap: wrap;
}
.cta-row.center { justify-content: center; }

/* ===== Hero visual: CSS MacBook with PBA mockup ===== */
.hero-visual {
  margin: 64px auto 0;
  max-width: 760px;
}

.mb-frame {
  position: relative;
  aspect-ratio: 16 / 10.4;
  background: linear-gradient(180deg, #1c1f26 0%, #0a0c10 100%);
  border-radius: var(--radius-lg);
  padding: 14px 14px 36px;
  box-shadow: var(--shadow-lg);
}

.mb-notch {
  position: absolute;
  top: 6px;
  left: 50%;
  transform: translateX(-50%);
  width: 90px;
  height: 6px;
  background: #2a2d34;
  border-radius: 3px;
}

.mb-screen {
  width: 100%;
  height: 100%;
  background:
    radial-gradient(800px 360px at 50% 30%, rgba(37, 69, 232, 0.18), transparent 70%),
    #000;
  border-radius: 10px;
  display: grid;
  place-items: center;
  overflow: hidden;
  position: relative;
}
.mb-screen::before {
  /* faint grid for "early boot" feel */
  content: '';
  position: absolute; inset: 0;
  background-image:
    linear-gradient(rgba(255,255,255,0.025) 1px, transparent 1px),
    linear-gradient(90deg, rgba(255,255,255,0.025) 1px, transparent 1px);
  background-size: 32px 32px;
}

.mb-base {
  position: absolute;
  bottom: 10px;
  left: 50%;
  transform: translateX(-50%);
  width: 70px;
  height: 4px;
  background: #1c1f26;
  border-radius: 4px;
}

.pba {
  position: relative;
  width: 280px;
  padding: 28px 24px;
  background: rgba(20, 25, 35, 0.85);
  backdrop-filter: blur(20px);
  border-radius: 14px;
  border: 1px solid rgba(255, 255, 255, 0.08);
  box-shadow: 0 20px 60px -10px rgba(0,0,0,0.6);
  color: #fff;
  text-align: center;
}

.pba-logo {
  width: 40px;
  height: 40px;
  margin: 0 auto 14px;
  background: linear-gradient(135deg, var(--accent), var(--accent-dark));
  border-radius: 9px;
  display: grid;
  place-items: center;
  font-weight: 700;
  font-size: 14px;
  letter-spacing: 0.5px;
  box-shadow: 0 6px 18px -6px rgba(37, 69, 232, 0.8);
}

.pba-title {
  font-size: 18px;
  margin: 0 0 4px;
  color: #fff;
  letter-spacing: -0.01em;
}
.pba-sub {
  font-size: 13px;
  color: rgba(255, 255, 255, 0.6);
  margin: 0 0 18px;
}

.pba-pin {
  display: flex;
  justify-content: center;
  gap: 10px;
  margin-bottom: 18px;
}
.pba-pin .dot {
  width: 14px;
  height: 14px;
  border-radius: 50%;
  border: 1.5px solid rgba(255, 255, 255, 0.35);
}
.pba-pin .dot.filled {
  background: var(--accent);
  border-color: var(--accent);
  box-shadow: 0 0 12px rgba(37, 69, 232, 0.6);
}

.pba-btn {
  width: 100%;
  background: var(--accent);
  color: #fff;
  border: none;
  border-radius: 8px;
  padding: 10px;
  font-weight: 600;
  font-size: 14px;
  cursor: pointer;
}
.pba-foot {
  margin: 14px 0 0;
  font-size: 11px;
  color: rgba(255, 255, 255, 0.4);
  letter-spacing: 0.04em;
}

/* ==========================================================================
   Trust strip
   ========================================================================== */
.trust-strip {
  padding: 48px 0;
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
  background: var(--bg);
}
.trust-label {
  text-align: center;
  font-size: 12px;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.14em;
  color: var(--muted);
  margin: 0 0 22px;
}
.trust-logos {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  justify-content: center;
  align-items: center;
  flex-wrap: wrap;
  gap: 40px;
}
.trust-logos li {
  font-size: 16px;
  font-weight: 600;
  color: var(--muted);
  letter-spacing: -0.01em;
  opacity: 0.75;
}

/* ==========================================================================
   Section base
   ========================================================================== */
.section { padding: 96px 0; }
.section-alt { background: var(--bg-alt); }

.section h2 {
  font-size: clamp(28px, 3.8vw, 44px);
  line-height: 1.1;
  margin: 0 auto 16px;
  max-width: 760px;
  letter-spacing: -0.02em;
}
.section h2.center { text-align: center; }

/* ==========================================================================
   How it works (3-step flow)
   ========================================================================== */
.flow {
  list-style: none;
  margin: 56px 0 0;
  padding: 0;
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 28px;
  position: relative;
}

.flow-step {
  background: #fff;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 32px 28px;
  position: relative;
}

.flow-num {
  font-family: var(--font-mono);
  font-size: 13px;
  font-weight: 600;
  color: var(--accent);
  letter-spacing: 0.06em;
  margin-bottom: 18px;
}

.flow-step h3 {
  font-size: 20px;
  margin: 0 0 8px;
}
.flow-step p {
  margin: 0;
  color: var(--ink-soft);
  font-size: 15.5px;
}

/* ==========================================================================
   Features (alternating image+text rows)
   ========================================================================== */
.feature-row {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 72px;
  align-items: center;
  padding: 56px 0;
}
.feature-row + .feature-row { border-top: 1px solid var(--line-soft); }
.feature-row.reverse .feature-text { order: 2; }
.feature-row.reverse .feature-art  { order: 1; }

.feature-text h2 {
  font-size: clamp(26px, 3vw, 36px);
  text-align: left;
  margin: 0 0 16px;
  max-width: 480px;
}
.feature-text p {
  font-size: 16.5px;
  color: var(--ink-soft);
  margin: 0 0 12px;
  max-width: 480px;
}

/* ===== Feature art cards ===== */
.feature-art { display: flex; justify-content: center; }
.art-card {
  width: 100%;
  max-width: 420px;
  background: #fff;
  border: 1px solid var(--line);
  border-radius: var(--radius-lg);
  padding: 32px;
  box-shadow: var(--shadow-md);
  min-height: 240px;
}

/* Lock card */
.art-lock {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  text-align: center;
  background: linear-gradient(160deg, #fff 0%, var(--accent-soft) 100%);
}
.art-shield { font-size: 72px; margin-bottom: 18px; }
.art-line {
  width: 70%;
  height: 8px;
  background: rgba(10, 14, 26, 0.08);
  border-radius: 4px;
  margin: 6px 0;
}
.art-line.short { width: 45%; }

/* Speed bars */
.art-speed { display: flex; flex-direction: column; gap: 14px; }
.speed-bar {
  position: relative;
  height: 36px;
  background: var(--bg-alt);
  border-radius: 8px;
  overflow: hidden;
}
.speed-bar span {
  display: block;
  height: 100%;
  background: linear-gradient(90deg, var(--accent), var(--accent-dark));
  border-radius: 8px;
}
.speed-bar em {
  position: absolute;
  top: 50%; left: 14px;
  transform: translateY(-50%);
  font-style: normal;
  font-weight: 600;
  font-size: 13px;
  color: #fff;
  mix-blend-mode: difference;
}
.speed-foot {
  margin: 6px 0 0;
  font-size: 12px;
  color: var(--muted);
  text-align: center;
}

/* Identity card */
.art-id { display: flex; flex-direction: column; gap: 8px; }
.id-row {
  display: grid;
  grid-template-columns: 32px 1fr 16px;
  align-items: center;
  gap: 14px;
  padding: 12px 14px;
  border-radius: 8px;
  background: var(--bg-alt);
  font-size: 14.5px;
  font-weight: 500;
}
.id-key { font-size: 18px; }
.id-dot {
  width: 8px; height: 8px;
  border-radius: 50%;
  background: var(--success);
}

/* Events card */
.art-events {
  font-family: var(--font-mono);
  font-size: 13px;
  display: flex;
  flex-direction: column;
  gap: 8px;
}
.ev {
  display: grid;
  grid-template-columns: 76px 60px 1fr;
  gap: 10px;
  align-items: center;
  padding: 8px 0;
  border-bottom: 1px solid var(--line-soft);
}
.ev:last-child { border-bottom: none; }
.ev-time { color: var(--muted); }
.ev-tag {
  text-align: center;
  font-size: 11px;
  padding: 2px 6px;
  border-radius: 4px;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.05em;
}
.ev-tag.ok   { background: rgba(15, 138, 74, 0.10); color: var(--success); }
.ev-tag.warn { background: rgba(183, 106, 0, 0.10); color: var(--warn); }
.ev-tag.err  { background: rgba(192, 57, 43, 0.10);  color: var(--danger); }

/* ==========================================================================
   Use cases
   ========================================================================== */
.usecase-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 18px;
  margin-top: 48px;
}
.usecase {
  background: #fff;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 24px;
}
.usecase h3 { font-size: 17px; margin: 0 0 8px; }
.usecase p { margin: 0; color: var(--ink-soft); font-size: 15px; }

/* ==========================================================================
   Quote
   ========================================================================== */
.quote {
  margin: 0 auto;
  max-width: 720px;
  text-align: center;
}
.quote blockquote {
  margin: 0 0 22px;
  font-size: clamp(20px, 2.6vw, 28px);
  line-height: 1.4;
  font-weight: 500;
  letter-spacing: -0.01em;
  color: var(--ink);
}
.quote figcaption {
  font-size: 14px;
  color: var(--muted);
}
.quote figcaption strong { color: var(--ink-soft); }

/* ==========================================================================
   FAQ
   ========================================================================== */
.faq {
  background: #fff;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 18px 22px;
  margin-bottom: 12px;
}
.faq summary {
  cursor: pointer;
  font-weight: 600;
  font-size: 16.5px;
  color: var(--ink);
  list-style: none;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
}
.faq summary::-webkit-details-marker { display: none; }
.faq summary::after {
  content: '+';
  font-size: 22px;
  font-weight: 400;
  color: var(--muted);
  transition: transform .2s;
}
.faq[open] summary::after { content: '–'; }
.faq p {
  margin: 12px 0 0;
  color: var(--ink-soft);
  font-size: 15.5px;
}

/* ==========================================================================
   Final CTA
   ========================================================================== */
.cta-section {
  padding: 96px 0;
  background:
    radial-gradient(700px 320px at 50% 0%, rgba(37, 69, 232, 0.18), transparent 70%),
    var(--bg-dark);
  color: #fff;
}
.cta-section h2 {
  color: #fff;
  font-size: clamp(30px, 4vw, 48px);
  margin: 0 auto 16px;
}
.cta-section .lede {
  color: rgba(255, 255, 255, 0.7);
  margin: 0 auto 32px;
}
.cta-section .btn.ghost {
  color: #fff;
  border-color: rgba(255, 255, 255, 0.25);
}
.cta-section .btn.ghost:hover {
  background: rgba(255, 255, 255, 0.08);
  border-color: rgba(255, 255, 255, 0.5);
}

/* ==========================================================================
   Footer
   ========================================================================== */
.site-footer {
  background: var(--bg-dark);
  color: rgba(255, 255, 255, 0.7);
  padding: 56px 0 40px;
}
.footer-inner {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  gap: 32px;
  flex-wrap: wrap;
}
.footer-brand {
  display: flex;
  align-items: center;
  gap: 10px;
  margin: 0 0 12px;
  color: #fff;
  font-size: 15px;
}
.footer-brand .brand-mark { color: #fff; }
.footer-meta {
  margin: 0;
  font-size: 13px;
  line-height: 1.7;
  max-width: 580px;
}
.footer-links {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 8px;
  margin: 0;
  padding: 0;
  font-size: 14px;
}
.footer-links a { color: rgba(255, 255, 255, 0.7); }
.footer-links a:hover { color: #fff; text-decoration: none; }

/* ==========================================================================
   Responsive
   ========================================================================== */
@media (max-width: 880px) {
  .nav-links { display: none; }
  .feature-row { grid-template-columns: 1fr; gap: 36px; padding: 40px 0; }
  .feature-row.reverse .feature-text { order: 1; }
  .feature-row.reverse .feature-art  { order: 2; }
  .flow { grid-template-columns: 1fr; }
  .hero { padding: 56px 0 40px; }
  .hero-visual { margin-top: 40px; }
  .section { padding: 64px 0; }
  .footer-inner { flex-direction: column; }
  .footer-links { flex-direction: row; flex-wrap: wrap; gap: 16px; }
}