/* ---------- Design tokens ---------- */
:root {
  --radius: 20px;
  --maxw: 640px;
  --font-ui: "Inter", system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
  --font-mono: "JetBrains Mono", "SFMono-Regular", ui-monospace, Menlo, monospace;
  --transition: 220ms cubic-bezier(0.4, 0, 0.2, 1);
}

/* Dark (default) */
[data-theme="dark"] {
  --bg-grad-a: #0f1117;
  --bg-grad-b: #14171f;
  --card: #171a22;
  --card-border: rgba(255, 255, 255, 0.06);
  --text: #e7e9ee;
  --muted: #8b90a0;
  --accent: #7c6cff;
  --accent-soft: rgba(124, 108, 255, 0.14);
  --shadow: 0 24px 60px -20px rgba(0, 0, 0, 0.6);
  --btn-fg: #e7e9ee;
  --btn-bg: rgba(255, 255, 255, 0.04);
  --btn-bg-hover: rgba(255, 255, 255, 0.08);
}

/* Light */
[data-theme="light"] {
  --bg-grad-a: #f6f7fb;
  --bg-grad-b: #eef0f7;
  --card: #ffffff;
  --card-border: rgba(15, 17, 23, 0.06);
  --text: #171a22;
  --muted: #6b7180;
  --accent: #6451f0;
  --accent-soft: rgba(100, 81, 240, 0.1);
  --shadow: 0 24px 50px -24px rgba(31, 33, 48, 0.28);
  --btn-fg: #171a22;
  --btn-bg: rgba(15, 17, 23, 0.03);
  --btn-bg-hover: rgba(15, 17, 23, 0.07);
}

/* ---------- Reset ---------- */
*,
*::before,
*::after {
  box-sizing: border-box;
}

html,
body {
  margin: 0;
  height: 100%;
}

body {
  font-family: var(--font-ui);
  color: var(--text);
  background:
    radial-gradient(120% 120% at 50% 0%, var(--bg-grad-b), var(--bg-grad-a));
    background-attachment: fixed;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: clamp(16px, 4vw, 48px);
  transition: background-color var(--transition), color var(--transition);
}

/* ---------- Card ---------- */
.card {
  position: relative;
  width: 100%;
  max-width: var(--maxw);
  background: var(--card);
  border: 1px solid var(--card-border);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  padding: clamp(28px, 5vw, 56px) clamp(24px, 5vw, 56px) clamp(32px, 5vw, 48px);
  text-align: center;
  transition: background-color var(--transition), border-color var(--transition);
}

/* ---------- Theme toggle ---------- */
.theme-toggle {
  position: absolute;
  top: 20px;
  right: 20px;
  width: 40px;
  height: 40px;
  display: grid;
  place-items: center;
  border: 1px solid var(--card-border);
  border-radius: 12px;
  background: var(--btn-bg);
  color: var(--text);
  cursor: pointer;
  transition: background-color var(--transition), transform var(--transition);
}
.theme-toggle:hover {
  background: var(--btn-bg-hover);
}
.theme-toggle:active {
  transform: scale(0.94);
}
.theme-toggle:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 2px;
}

.icon {
  width: 20px;
  height: 20px;
  fill: none;
  stroke: currentColor;
  stroke-width: 1.8;
}
/* Show sun in dark mode (action: go light), moon in light mode. */
.icon-sun {
  display: none;
}
.icon-moon {
  display: block;
}
[data-theme="dark"] .icon-sun {
  display: block;
}
[data-theme="dark"] .icon-moon {
  display: none;
}

/* ---------- Title ---------- */
.title {
  margin: 0 0 28px;
  font-size: clamp(1.4rem, 1rem + 2vw, 2rem);
  font-weight: 700;
  letter-spacing: -0.02em;
}

/* ---------- Countdown ---------- */
.countdown {
  display: flex;
  align-items: flex-start;
  justify-content: center;
  gap: clamp(6px, 1.5vw, 14px);
  margin: 8px 0 28px;
}

.seg {
  display: flex;
  flex-direction: column;
  align-items: center;
  min-width: clamp(64px, 18vw, 110px);
  padding: 18px 8px 14px;
  background: var(--accent-soft);
  border-radius: 14px;
}

.value {
  font-family: var(--font-mono);
  font-weight: 700;
  font-size: clamp(2rem, 1.4rem + 4vw, 3.4rem);
  line-height: 1;
  letter-spacing: -0.02em;
  font-variant-numeric: tabular-nums;
}

.label {
  margin-top: 10px;
  font-size: 0.72rem;
  font-weight: 500;
  text-transform: uppercase;
  letter-spacing: 0.12em;
  color: var(--muted);
}

.colon {
  align-self: center;
  margin-top: -18px;
  font-family: var(--font-mono);
  font-weight: 700;
  font-size: clamp(1.6rem, 1.2rem + 2vw, 2.6rem);
  color: var(--muted);
}

/* ---------- Ends-at line ---------- */
.ends-at {
  margin: 0 0 26px;
  color: var(--muted);
  font-size: 0.95rem;
}

.done-note {
  margin: 0 0 26px;
  font-weight: 600;
  color: var(--accent);
  letter-spacing: 0.02em;
}

/* ---------- Contact ---------- */
.contact {
  display: inline-block;
  padding: 12px 26px;
  border-radius: 999px;
  background: var(--accent);
  color: #ffffff;
  font-weight: 600;
  font-size: 0.95rem;
  text-decoration: none;
  letter-spacing: 0.01em;
  transition: transform var(--transition), filter var(--transition),
    background-color var(--transition);
}
.contact:hover {
  transform: translateY(-1px);
  filter: brightness(1.08);
}
.contact:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 3px;
}

/* ---------- Responsive ---------- */
@media (max-width: 480px) {
  .countdown {
    flex-wrap: wrap;
    gap: 8px;
  }
  .seg {
    min-width: 0;
    flex: 1 1 calc(50% - 12px);
  }
  .colon {
    display: none;
  }
}

/* ---------- Accessibility ---------- */
@media (prefers-reduced-motion: reduce) {
  * {
    transition: none !important;
  }
}