/* ============================================================
   main.css — TZ-Convert
   Material-style base, theme variables (dark/light), layout.
   ============================================================ */

/* ── Dark theme (default) ────────────────────────────────── */
:root {
  --bg:            #0a0a0a;
  --surface:       #1c1917;
  --surface-2:     #231f1d;
  --surface-3:     #2d2926;
  --accent:        #6829B1;
  --accent-h:      #7B32CC;
  --accent-dim:    #3D1870;
  --accent-glow:   rgba(104, 41, 177, 0.25);
  --text:          #e2e8f0;
  --text-dim:      #94a3b8;
  --text-muted:    #64748b;
  --border:        #2d2926;
  --divider:       rgba(255, 255, 255, 0.05);
  --green:         #4ade80;
  --red:           #f87171;
  /* Material elevation shadows */
  --elev-1: 0 1px 3px rgba(0,0,0,.5),  0 1px 2px rgba(0,0,0,.4);
  --elev-2: 0 3px 10px rgba(0,0,0,.55), 0 2px 4px rgba(0,0,0,.4);
  --elev-3: 0 8px 28px rgba(0,0,0,.65), 0 4px 8px rgba(0,0,0,.45);
  --elev-accent: 0 3px 14px rgba(104,41,177,.45);
  --radius:    12px;
  --radius-sm: 8px;
  --radius-lg: 16px;
  --font: 'Inter', system-ui, -apple-system, sans-serif;
  --mono: 'JetBrains Mono', 'Fira Code', 'Cascadia Code', monospace;
  --t: 0.2s ease;
}

/* ── Light theme ─────────────────────────────────────────── */
[data-theme="light"] {
  --bg:          #f0ecfb;
  --surface:     #ffffff;
  --surface-2:   #ede8f9;
  --surface-3:   #e4dcf5;
  --accent-glow: rgba(104, 41, 177, 0.15);
  --text:        #1a1228;
  --text-dim:    #5a4b72;
  --text-muted:  #8b79a8;
  --border:      #d8d0ed;
  --divider:     rgba(0, 0, 0, 0.06);
  --green:       #16a34a;
  --red:         #dc2626;
  --elev-1: 0 1px 3px rgba(104,41,177,.10), 0 1px 2px rgba(0,0,0,.05);
  --elev-2: 0 3px 10px rgba(104,41,177,.13), 0 2px 4px rgba(0,0,0,.06);
  --elev-3: 0 8px 28px rgba(104,41,177,.18), 0 4px 8px rgba(0,0,0,.08);
  --elev-accent: 0 3px 14px rgba(104,41,177,.38);
}

/* ── Theme transition (smooth switch) ────────────────────── */
*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
  transition:
    background-color var(--t),
    border-color var(--t),
    box-shadow var(--t),
    color var(--t);
}

/* Disable transition on SVG elements (icons should flip instantly) */
svg, svg * { transition: none; }

html { font-size: 16px; -webkit-text-size-adjust: 100%; }

body {
  background: var(--bg);
  color: var(--text);
  font-family: var(--font);
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  line-height: 1.5;
}

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

/* ── Header ──────────────────────────────────────────────── */
#site-header {
  background: var(--surface);
  box-shadow: var(--elev-1);
  padding: 0 24px;
  height: 56px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-shrink: 0;
  position: sticky;
  top: 0;
  z-index: 200;
}

.header-left {
  display: flex;
  align-items: center;
  gap: 10px;
}

.header-logo {
  width: 26px;
  height: 26px;
  border-radius: 4px;
}

.header-title {
  font-size: 1.1rem;
  font-weight: 700;
  letter-spacing: -0.01em;
  color: var(--text);
}

.header-right {
  display: flex;
  align-items: center;
  gap: 14px;
}

#live-clock {
  font-family: var(--mono);
  font-size: 0.78rem;
  color: var(--text-muted);
  letter-spacing: 0.02em;
}

/* ── Theme toggle button ─────────────────────────────────── */
.theme-toggle {
  background: transparent;
  border: none;
  border-radius: 50%;
  color: var(--text-dim);
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  height: 36px;
  width: 36px;
  flex-shrink: 0;
  /* No transition override needed — transition set above */
}
.theme-toggle:hover {
  background: var(--surface-2);
  color: var(--accent);
}
.theme-toggle svg {
  width: 19px;
  height: 19px;
  transition: none;
}

/* Show moon in dark, sun in light */
[data-theme="dark"]  .icon-sun  { display: none; }
[data-theme="dark"]  .icon-moon { display: block; }
[data-theme="light"] .icon-moon { display: none; }
[data-theme="light"] .icon-sun  { display: block; }

/* ── Tab navigation ──────────────────────────────────────── */
#tab-nav {
  background: var(--surface);
  border-bottom: 1px solid var(--border);
  padding: 0 20px;
  display: flex;
  gap: 2px;
  flex-shrink: 0;
  overflow-x: auto;
  scrollbar-width: none;
}
#tab-nav::-webkit-scrollbar { display: none; }

.tab-btn {
  background: transparent;
  border: none;
  border-bottom: 2px solid transparent;
  color: var(--text-muted);
  cursor: pointer;
  font-family: var(--font);
  font-size: 0.875rem;
  font-weight: 500;
  height: 44px;
  padding: 0 16px;
  white-space: nowrap;
  letter-spacing: 0.01em;
}
.tab-btn:hover { color: var(--text-dim); }
.tab-btn.active {
  color: var(--accent);
  border-bottom-color: var(--accent);
}

/* ── Content area ────────────────────────────────────────── */
#content {
  flex: 1;
  max-width: 1000px;
  width: 100%;
  margin: 0 auto;
  padding: 24px 16px;
}

/* ── Panel ───────────────────────────────────────────────── */
.panel { animation: fadeIn 0.15s ease; }

@keyframes fadeIn {
  from { opacity: 0; transform: translateY(5px); }
  to   { opacity: 1; transform: translateY(0); }
}

.section-title {
  font-size: 1rem;
  font-weight: 600;
  color: var(--text);
  margin-bottom: 14px;
}

/* ── Toast ───────────────────────────────────────────────── */
.toast {
  position: fixed;
  bottom: 24px;
  left: 50%;
  transform: translateX(-50%) translateY(80px);
  background: var(--surface-3);
  color: var(--text);
  border-radius: var(--radius-sm);
  box-shadow: var(--elev-3);
  font-size: 0.875rem;
  padding: 10px 20px;
  pointer-events: none;
  opacity: 0;
  transition: opacity 0.2s ease, transform 0.2s ease;
  z-index: 999;
  white-space: nowrap;
}
.toast.show {
  opacity: 1;
  transform: translateX(-50%) translateY(0);
}

/* ── Footer ──────────────────────────────────────────────── */
#site-footer {
  border-top: 1px solid var(--border);
  padding: 12px 24px;
  display: flex;
  justify-content: space-between;
  font-size: 0.78rem;
  color: var(--text-muted);
  flex-shrink: 0;
}

/* ── Responsive ──────────────────────────────────────────── */
@media (max-width: 600px) {
  #site-header { padding: 0 14px; }
  #content { padding: 14px 10px; }
  #live-clock { display: none; }
}