/* ============================================================
   LinkTiles — Shared Design System
   site.css — linked from all pages
   ============================================================ */

/* ------------------------------------------------------------
   Custom Properties
   ------------------------------------------------------------ */
:root {
  --brand:        #55BAD3;
  --brand-dark:   #3da8c2;
  --brand-text:   #2a8fa8;
  --brand-light:  #e5f7fb;
  --brand-subtle: rgba(85, 186, 211, 0.13);

  --ink:          #1a1830;
  --ink-muted:    #6b6880;
  --border:       #e0e0e0;
  --bg:           #ffffff;
  --bg-subtle:    #f7f7f7;

  --font-sans:    'DM Sans', sans-serif;
  --font-mono:    'DM Mono', monospace;

  --radius-sm:    8px;
  --radius-md:    12px;
  --radius-lg:    16px;

  --shadow-card:  0 1px 4px rgba(26, 24, 48, 0.06), 0 4px 16px rgba(26, 24, 48, 0.04);
}

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

body {
  font-family: var(--font-sans);
  background: var(--bg);
  color: var(--ink);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}

a { color: inherit; text-decoration: none; }
img, svg { display: block; }

/* ------------------------------------------------------------
   Layout
   ------------------------------------------------------------ */
.container {
  max-width: 960px;
  margin: 0 auto;
  padding: 0 24px;
}

.container-narrow {
  max-width: 680px;
  margin: 0 auto;
  padding: 0 24px;
}

.section-rule {
  border: none;
  border-top: 1px solid var(--border);
  margin: 0;
}

/* ------------------------------------------------------------
   Buttons
   ------------------------------------------------------------ */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  border: none;
  border-radius: var(--radius-sm);
  font-family: var(--font-sans);
  font-size: 15px;
  font-weight: 500;
  cursor: pointer;
  transition: background 0.15s, transform 0.1s, box-shadow 0.15s;
  text-decoration: none;
  white-space: nowrap;
  line-height: 1;
}

.btn-primary {
  background: var(--brand-text);
  color: #fff;
  padding: 11px 22px;
}
.btn-primary:hover  { background: var(--brand-dark); }
.btn-primary:active { transform: scale(0.98); }

.btn-ghost {
  background: transparent;
  color: var(--ink);
  padding: 11px 22px;
  border: 1px solid var(--border);
}
.btn-ghost:hover { background: var(--bg-subtle); border-color: #aaa; }

.btn-lg {
  padding: 14px 28px;
  font-size: 16px;
  border-radius: var(--radius-md);
}

/* ------------------------------------------------------------
   Brand Logo
   ------------------------------------------------------------ */
.brand-logo {
  display: flex;
  align-items: center;
  gap: 10px;
  text-decoration: none;
}

.brand-logo img {
  width: 28px;
  height: 28px;
}

.brand-logo-name {
  font-family: var(--font-mono);
  font-size: 16px;
  font-weight: 500;
  color: var(--ink);
  letter-spacing: 0.02em;
}

/* ------------------------------------------------------------
   Nav
   ------------------------------------------------------------ */
.site-nav {
  position: sticky;
  top: 0;
  z-index: 50;
  background: var(--bg);
  border-bottom: 1px solid transparent;
  transition: border-color 0.2s, box-shadow 0.2s;
}

.site-nav.scrolled {
  border-bottom-color: var(--border);
  box-shadow: 0 1px 8px rgba(26, 24, 48, 0.05);
}

.nav-inner {
  max-width: 960px;
  margin: 0 auto;
  padding: 0 24px;
  height: 60px;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 24px;
}

.nav-link {
  font-size: 14px;
  font-weight: 500;
  color: var(--ink-muted);
  transition: color 0.15s;
}

.nav-link:hover { color: var(--brand-text); }

/* ------------------------------------------------------------
   Section Labels
   ------------------------------------------------------------ */
.section-label {
  font-family: var(--font-mono);
  font-size: 12px;
  font-weight: 500;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--brand-text);
  margin-bottom: 28px;
}

/* ------------------------------------------------------------
   Feature Cards
   ------------------------------------------------------------ */
.features-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 16px;
}

.feature-card {
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  padding: 24px;
  transition: border-color 0.15s, box-shadow 0.15s;
}

.feature-card:hover {
  border-color: #c2e8f0;
  box-shadow: var(--shadow-card);
}

.feature-icon {
  width: 36px;
  height: 36px;
  border-radius: var(--radius-sm);
  background: var(--brand-light);
  color: var(--brand);
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 16px;
  flex-shrink: 0;
}

.feature-title {
  font-size: 16px;
  font-weight: 500;
  color: var(--ink);
  margin-bottom: 8px;
}

.feature-desc {
  font-size: 14px;
  color: var(--ink-muted);
  line-height: 1.6;
}

/* ------------------------------------------------------------
   Latest Update Card
   ------------------------------------------------------------ */
.update-card {
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 28px 32px;
  background: var(--bg-subtle);
}

.update-header {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  margin-bottom: 20px;
  gap: 16px;
  flex-wrap: wrap;
}

.update-version {
  font-family: var(--font-mono);
  font-size: 14px;
  font-weight: 500;
  color: var(--ink);
  letter-spacing: 0.02em;
  margin-right: 10px;
}

.update-date {
  font-size: 13px;
  color: var(--ink-muted);
}

.update-link {
  display: inline-flex;
  align-items: center;
  gap: 5px;
  font-size: 14px;
  font-weight: 500;
  color: var(--brand-text);
  transition: color 0.15s, gap 0.15s;
  flex-shrink: 0;
}

.update-link:hover {
  color: var(--brand-dark);
  gap: 8px;
}

.update-bullets {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.update-bullets li {
  font-size: 15px;
  color: var(--ink);
  padding-left: 16px;
  position: relative;
  line-height: 1.5;
}

.update-bullets li::before {
  content: '';
  position: absolute;
  left: 0;
  top: 8px;
  width: 5px;
  height: 5px;
  border-radius: 50%;
  background: var(--brand);
}

/* ------------------------------------------------------------
   Footer
   ------------------------------------------------------------ */
.site-footer {
  border-top: 1px solid var(--border);
  padding: 32px 24px;
  text-align: center;
}

.footer-links {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 24px;
  flex-wrap: wrap;
  font-size: 14px;
  color: var(--ink-muted);
}

.footer-links a:hover { color: var(--brand-text); }

/* ------------------------------------------------------------
   Responsive
   ------------------------------------------------------------ */
@media (max-width: 700px) {
  .features-grid { grid-template-columns: 1fr; }
}