/* ============================================================
   style.css — Secure-Smart-Sync Documentation Site
   Dark theme · Purple accent · Inter font · No emojis
   ============================================================ */

@import url('https://fonts.googleapis.com/css2?family=Inter:wght@300;400;500;600;700&family=JetBrains+Mono:wght@400;500&display=swap');

/* ── Design tokens ───────────────────────────────────────── */
:root {
  --bg-base:        #0f1117;
  --bg-surface:     #161b27;
  --bg-elevated:    #1c2236;
  --bg-hover:       #212840;

  --purple-core:    #7c5cbf;
  --purple-light:   #9b7cd6;
  --purple-dim:     #4a3878;
  --purple-faint:   rgba(124, 92, 191, 0.12);
  --purple-border:  rgba(124, 92, 191, 0.30);

  --text-primary:   #e8eaf0;
  --text-secondary: #9aa3b8;
  --text-muted:     #5a6380;
  --text-code:      #c4aef5;

  --border:         rgba(255, 255, 255, 0.07);
  --border-strong:  rgba(255, 255, 255, 0.12);

  --radius-sm:  6px;
  --radius-md:  10px;
  --radius-lg:  16px;

  --transition: 200ms ease;
  --transition-slow: 400ms ease;

  --font-sans: 'Inter', system-ui, sans-serif;
  --font-mono: 'JetBrains Mono', 'Fira Code', monospace;

  --nav-height: 60px;
  --content-max: 860px;
  --content-wide: 1100px;
}

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

html { scroll-behavior: smooth; font-size: 16px; }

body {
  font-family: var(--font-sans);
  background: var(--bg-base);
  color: var(--text-primary);
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
  min-height: 100vh;
}

/* ── Typography ──────────────────────────────────────────── */
h1, h2, h3, h4, h5, h6 {
  font-weight: 600;
  line-height: 1.3;
  color: var(--text-primary);
  letter-spacing: -0.01em;
}

h1 { font-size: clamp(1.8rem, 4vw, 2.8rem); }
h2 { font-size: clamp(1.3rem, 3vw, 1.9rem); }
h3 { font-size: 1.15rem; }
h4 { font-size: 1rem; }

p { color: var(--text-secondary); font-size: 0.975rem; }

a {
  color: var(--purple-light);
  text-decoration: none;
  transition: color var(--transition);
}
a:hover { color: #c4aef5; }

code, kbd {
  font-family: var(--font-mono);
  font-size: 0.875em;
  background: rgba(124, 92, 191, 0.15);
  color: var(--text-code);
  padding: 2px 6px;
  border-radius: 4px;
  border: 1px solid var(--purple-border);
}

pre {
  font-family: var(--font-mono);
  font-size: 0.875rem;
  background: var(--bg-surface);
  border: 1px solid var(--border-strong);
  border-radius: var(--radius-md);
  padding: 1.25rem 1.5rem;
  overflow-x: auto;
  color: var(--text-primary);
  line-height: 1.6;
}
pre code {
  background: none;
  border: none;
  padding: 0;
  color: inherit;
  font-size: inherit;
}

hr {
  border: none;
  border-top: 1px solid var(--border);
  margin: 2rem 0;
}

ul, ol { padding-left: 1.5rem; }
li { color: var(--text-secondary); font-size: 0.975rem; margin-bottom: 0.35rem; }

strong { color: var(--text-primary); font-weight: 600; }

/* ── Navigation ──────────────────────────────────────────── */
.nav {
  position: fixed;
  top: 0; left: 0; right: 0;
  height: var(--nav-height);
  background: rgba(15, 17, 23, 0.90);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border);
  z-index: 1000;
  display: flex;
  align-items: center;
}

.nav-inner {
  width: 100%;
  max-width: var(--content-wide);
  margin: 0 auto;
  padding: 0 1.5rem;
  display: flex;
  align-items: center;
  gap: 1rem;
}

.nav-logo {
  display: flex;
  align-items: center;
  gap: 0.6rem;
  text-decoration: none;
  flex-shrink: 0;
}
.nav-logo svg { width: 26px; height: 26px; }
.nav-logo-text {
  font-size: 0.95rem;
  font-weight: 600;
  color: var(--text-primary);
  white-space: nowrap;
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 0.1rem;
  list-style: none;
  padding: 0;
  margin: 0 auto;
}

.nav-links a {
  display: block;
  padding: 0.4rem 0.75rem;
  font-size: 0.875rem;
  font-weight: 500;
  color: var(--text-secondary);
  border-radius: var(--radius-sm);
  transition: color var(--transition), background var(--transition);
  white-space: nowrap;
}
.nav-links a:hover,
.nav-links a.active {
  color: var(--text-primary);
  background: var(--bg-hover);
}
.nav-links a.active { color: var(--purple-light); }

.nav-cta {
  margin-left: auto;
  flex-shrink: 0;
}

.nav-hamburger {
  display: none;
  flex-direction: column;
  gap: 5px;
  cursor: pointer;
  padding: 6px;
  margin-left: auto;
  background: none;
  border: none;
}
.nav-hamburger span {
  display: block;
  width: 20px; height: 2px;
  background: var(--text-secondary);
  border-radius: 2px;
  transition: transform var(--transition), opacity var(--transition);
}

/* ── Buttons ─────────────────────────────────────────────── */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.55rem 1.2rem;
  font-family: var(--font-sans);
  font-size: 0.875rem;
  font-weight: 500;
  border-radius: var(--radius-md);
  border: 1px solid transparent;
  cursor: pointer;
  text-decoration: none;
  transition: background var(--transition), border-color var(--transition),
              color var(--transition), transform 120ms ease;
  white-space: nowrap;
}
.btn:hover { transform: translateY(-1px); }
.btn:active { transform: translateY(0); }

.btn-primary {
  background: var(--purple-core);
  border-color: var(--purple-core);
  color: #fff;
}
.btn-primary:hover { background: var(--purple-light); border-color: var(--purple-light); color: #fff; }

.btn-outline {
  background: transparent;
  border-color: var(--border-strong);
  color: var(--text-secondary);
}
.btn-outline:hover { border-color: var(--purple-border); color: var(--text-primary); background: var(--purple-faint); }

.btn-ghost {
  background: transparent;
  border-color: transparent;
  color: var(--text-secondary);
}
.btn-ghost:hover { color: var(--text-primary); background: var(--bg-hover); }

.btn svg { width: 15px; height: 15px; flex-shrink: 0; }

/* ── Layout utilities ────────────────────────────────────── */
.page-wrap {
  padding-top: var(--nav-height);
  min-height: 100vh;
}

.container {
  max-width: var(--content-max);
  margin: 0 auto;
  padding: 0 1.5rem;
}

.container-wide {
  max-width: var(--content-wide);
  margin: 0 auto;
  padding: 0 1.5rem;
}

.section { padding: 4rem 0; }
.section-sm { padding: 2rem 0; }
.section-lg { padding: 6rem 0; }

/* ── Cards ───────────────────────────────────────────────── */
.card {
  background: var(--bg-surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 1.5rem;
  transition: border-color var(--transition), background var(--transition);
}
.card:hover { border-color: var(--border-strong); }
.card-purple {
  border-color: var(--purple-border);
  background: linear-gradient(135deg, var(--bg-surface), rgba(124, 92, 191, 0.06));
}

/* ── Step / Flow ─────────────────────────────────────────── */
.step-flow {
  display: flex;
  flex-direction: column;
  gap: 0;
  position: relative;
}
.step-flow::before {
  content: '';
  position: absolute;
  left: 19px;
  top: 40px;
  bottom: 40px;
  width: 2px;
  background: linear-gradient(to bottom, var(--purple-dim), transparent);
}

.step-item {
  display: flex;
  gap: 1.25rem;
  padding: 1.25rem 0;
  opacity: 0;
  transform: translateY(18px);
  transition: opacity 0.5s ease, transform 0.5s ease;
}
.step-item.in-view { opacity: 1; transform: translateY(0); }

.step-num {
  flex-shrink: 0;
  width: 38px; height: 38px;
  border-radius: 50%;
  background: var(--bg-elevated);
  border: 2px solid var(--purple-dim);
  display: flex; align-items: center; justify-content: center;
  font-size: 0.8rem;
  font-weight: 700;
  color: var(--purple-light);
  position: relative;
  z-index: 1;
}

.step-body h3 { font-size: 1rem; margin-bottom: 0.3rem; }
.step-body p { font-size: 0.9rem; }

/* ── Info / Warning / Note callouts ─────────────────────── */
.callout {
  border-radius: var(--radius-md);
  padding: 1rem 1.2rem;
  border-left: 3px solid;
  margin: 1.25rem 0;
  display: flex;
  gap: 0.75rem;
  align-items: flex-start;
}
.callout svg { flex-shrink: 0; margin-top: 2px; }
.callout-body { flex: 1; }
.callout-body strong { display: block; font-size: 0.875rem; margin-bottom: 0.2rem; }
.callout-body p, .callout-body span { font-size: 0.875rem; }

.callout-info {
  background: rgba(96, 165, 250, 0.07);
  border-color: #60a5fa;
}
.callout-info svg { color: #60a5fa; }

.callout-warning {
  background: rgba(251, 191, 36, 0.07);
  border-color: #fbbf24;
}
.callout-warning svg { color: #fbbf24; }

.callout-success {
  background: rgba(52, 211, 153, 0.07);
  border-color: #34d399;
}
.callout-success svg { color: #34d399; }

.callout-error {
  background: rgba(248, 113, 113, 0.07);
  border-color: #f87171;
}
.callout-error svg { color: #f87171; }

/* ── Breadcrumb ──────────────────────────────────────────── */
.breadcrumb {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  font-size: 0.825rem;
  color: var(--text-muted);
  margin-bottom: 2rem;
  flex-wrap: wrap;
}
.breadcrumb a { color: var(--text-muted); }
.breadcrumb a:hover { color: var(--purple-light); }
.breadcrumb-sep { color: var(--text-muted); }

/* ── Page header ─────────────────────────────────────────── */
.page-header {
  padding: 3.5rem 0 2.5rem;
  border-bottom: 1px solid var(--border);
  margin-bottom: 3rem;
}
.page-header .badge {
  display: inline-block;
  font-size: 0.75rem;
  font-weight: 600;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: var(--purple-light);
  background: var(--purple-faint);
  border: 1px solid var(--purple-border);
  border-radius: 4px;
  padding: 3px 10px;
  margin-bottom: 1rem;
}
.page-header h1 { margin-bottom: 0.75rem; }
.page-header p { font-size: 1.05rem; max-width: 600px; }

/* ── Section titles ──────────────────────────────────────── */
.section-title { margin-bottom: 2rem; }
.section-title h2 { margin-bottom: 0.5rem; }
.section-title p { font-size: 0.975rem; }

/* ── FAQ / Accordion ─────────────────────────────────────── */
.accordion-item {
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  margin-bottom: 0.5rem;
  overflow: hidden;
  transition: border-color var(--transition);
}
.accordion-item:hover { border-color: var(--border-strong); }
.accordion-item.open { border-color: var(--purple-border); }

.accordion-trigger {
  width: 100%;
  background: var(--bg-surface);
  border: none;
  padding: 1rem 1.25rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
  cursor: pointer;
  color: var(--text-primary);
  font-size: 0.95rem;
  font-weight: 500;
  font-family: var(--font-sans);
  text-align: left;
  gap: 1rem;
  transition: background var(--transition);
}
.accordion-trigger:hover { background: var(--bg-hover); }
.accordion-icon {
  flex-shrink: 0;
  color: var(--text-muted);
  transition: transform var(--transition);
}
.accordion-item.open .accordion-icon { transform: rotate(180deg); }

.accordion-body {
  background: var(--bg-surface);
  max-height: 0;
  overflow: hidden;
  transition: max-height 0.35s ease, padding 0.25s ease;
}
.accordion-body-inner {
  padding: 0 1.25rem 1.25rem;
  border-top: 1px solid var(--border);
}
.accordion-body-inner p, .accordion-body-inner li { font-size: 0.9rem; }
.accordion-item.open .accordion-body { max-height: 800px; }

/* ── Table ───────────────────────────────────────────────── */
.table-wrap { overflow-x: auto; border-radius: var(--radius-md); border: 1px solid var(--border); }
table { width: 100%; border-collapse: collapse; }
thead { background: var(--bg-elevated); }
th {
  padding: 0.75rem 1rem;
  font-size: 0.8rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: var(--text-secondary);
  text-align: left;
  border-bottom: 1px solid var(--border);
}
td {
  padding: 0.75rem 1rem;
  font-size: 0.9rem;
  color: var(--text-secondary);
  border-bottom: 1px solid var(--border);
}
tbody tr:last-child td { border-bottom: none; }
tbody tr:hover td { background: var(--bg-hover); }

/* ── Tags / Badges ───────────────────────────────────────── */
.tag {
  display: inline-block;
  font-size: 0.75rem;
  font-weight: 500;
  padding: 2px 8px;
  border-radius: 4px;
}
.tag-purple { background: var(--purple-faint); color: var(--purple-light); border: 1px solid var(--purple-border); }
.tag-blue   { background: rgba(96,165,250,0.1); color: #93c5fd; border: 1px solid rgba(96,165,250,0.25); }
.tag-green  { background: rgba(52,211,153,0.1); color: #6ee7b7; border: 1px solid rgba(52,211,153,0.25); }
.tag-yellow { background: rgba(251,191,36,0.1);  color: #fde68a; border: 1px solid rgba(251,191,36,0.25); }
.tag-red    { background: rgba(248,113,113,0.1); color: #fca5a5; border: 1px solid rgba(248,113,113,0.25); }

/* ── Grid helpers ────────────────────────────────────────── */
.grid-2 { display: grid; grid-template-columns: repeat(2, 1fr); gap: 1.25rem; }
.grid-3 { display: grid; grid-template-columns: repeat(3, 1fr); gap: 1.25rem; }

/* ── Footer ──────────────────────────────────────────────── */
footer {
  border-top: 1px solid var(--border);
  padding: 2.5rem 0;
  margin-top: 4rem;
}
.footer-inner {
  max-width: var(--content-wide);
  margin: 0 auto;
  padding: 0 1.5rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 1rem;
}
.footer-logo { display: flex; align-items: center; gap: 0.5rem; }
.footer-logo svg { width: 20px; height: 20px; }
.footer-logo span { font-size: 0.875rem; font-weight: 600; color: var(--text-secondary); }
.footer-meta { font-size: 0.8rem; color: var(--text-muted); }
.footer-links { display: flex; gap: 1.25rem; }
.footer-links a { font-size: 0.825rem; color: var(--text-muted); }
.footer-links a:hover { color: var(--purple-light); }

/* ── Ko-fi button ────────────────────────────────────────── */
.kofi-btn {
  display: inline-flex;
  align-items: center;
  gap: 0.6rem;
  padding: 0.6rem 1.3rem;
  background: #29abe0;
  color: #fff;
  border-radius: var(--radius-md);
  font-weight: 600;
  font-size: 0.9rem;
  border: none;
  cursor: pointer;
  text-decoration: none;
  transition: background var(--transition), transform 120ms ease;
}
.kofi-btn:hover { background: #1f90c2; color: #fff; transform: translateY(-1px); }
.kofi-btn svg { width: 20px; height: 20px; }

/* ── Scroll-reveal ───────────────────────────────────────── */
.reveal {
  opacity: 0;
  transform: translateY(20px);
  transition: opacity 0.5s ease, transform 0.5s ease;
}
.reveal.in-view { opacity: 1; transform: translateY(0); }

/* ── Utility ─────────────────────────────────────────────── */
.text-purple { color: var(--purple-light); }
.text-muted  { color: var(--text-muted); }
.text-sm     { font-size: 0.875rem; }
.text-xs     { font-size: 0.8rem; }
.mt-1  { margin-top: 0.5rem; }
.mt-2  { margin-top: 1rem; }
.mt-3  { margin-top: 1.5rem; }
.mt-4  { margin-top: 2rem; }
.mb-1  { margin-bottom: 0.5rem; }
.mb-2  { margin-bottom: 1rem; }
.mb-3  { margin-bottom: 1.5rem; }
.mb-4  { margin-bottom: 2rem; }
.flex  { display: flex; }
.items-center { align-items: center; }
.gap-1 { gap: 0.5rem; }
.gap-2 { gap: 1rem; }

/* ── Scrollbar ───────────────────────────────────────────── */
::-webkit-scrollbar { width: 6px; height: 6px; }
::-webkit-scrollbar-track { background: var(--bg-base); }
::-webkit-scrollbar-thumb { background: var(--bg-elevated); border-radius: 3px; }
::-webkit-scrollbar-thumb:hover { background: var(--purple-dim); }

/* ── Mobile nav ──────────────────────────────────────────── */
@media (max-width: 768px) {
  .nav-links { display: none; position: fixed; top: var(--nav-height); left: 0; right: 0;
    flex-direction: column; background: var(--bg-surface); border-bottom: 1px solid var(--border);
    padding: 1rem; gap: 0.25rem; }
  .nav-links.open { display: flex; }
  .nav-links a { padding: 0.6rem 1rem; width: 100%; }
  .nav-cta { display: none; }
  .nav-hamburger { display: flex; }
  .grid-2, .grid-3 { grid-template-columns: 1fr; }
  .footer-inner { flex-direction: column; align-items: flex-start; }
  .footer-links { flex-wrap: wrap; }
}

@media (max-width: 520px) {
  .container, .container-wide { padding: 0 1rem; }
  .section { padding: 2.5rem 0; }
  .section-lg { padding: 3.5rem 0; }
  h1 { font-size: 1.7rem; }
}