:root {
  color-scheme: light;
  --bg: #eef3f8;
  --surface: #ffffff;
  --surface-soft: #f6f8fb;
  --ink: #101828;
  --muted: #475467;
  --line: #d0d5dd;
  --accent: #2563eb;
  --teal: #0f766e;
  --amber: #d97706;
  --violet: #6d28d9;
  --danger: #b42318;
  --shadow: 0 24px 60px rgba(16, 24, 40, 0.12);
}

* {
  box-sizing: border-box;
}

[hidden] {
  display: none !important;
}

body {
  margin: 0;
  min-height: 100vh;
  background: linear-gradient(135deg, #f8fbff 0%, #eef3f8 48%, #e8f1f4 100%);
  color: var(--ink);
  font-family:
    Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI",
    sans-serif;
}

button,
input,
select {
  font: inherit;
}

button {
  cursor: pointer;
}

.app-shell {
  min-height: 100vh;
  display: grid;
  place-items: center;
  padding: clamp(64px, 8vw, 92px) clamp(18px, 4vw, 56px);
}

.page-clock,
.page-date {
  position: fixed;
  z-index: 2;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: rgba(255, 255, 255, 0.9);
  color: var(--ink);
  box-shadow: 0 12px 34px rgba(16, 24, 40, 0.1);
  font-weight: 900;
  letter-spacing: 0;
  font-variant-numeric: tabular-nums;
  backdrop-filter: blur(12px);
}

.page-clock {
  top: 18px;
  right: 18px;
  padding: 12px 16px;
  font-size: clamp(1rem, 2vw, 1.35rem);
}

.page-date {
  left: 50%;
  bottom: 18px;
  transform: translateX(-50%);
  width: max-content;
  max-width: calc(100vw - 36px);
  padding: 11px 16px;
  color: var(--muted);
  font-size: clamp(0.92rem, 2vw, 1.1rem);
  text-align: center;
}

.countdown-panel {
  width: min(1040px, 100%);
  border: 1px solid var(--line);
  border-radius: 8px;
  background: rgba(255, 255, 255, 0.94);
  box-shadow: var(--shadow);
  padding: clamp(24px, 5vw, 54px);
}

.panel-header {
  display: grid;
  grid-template-columns: minmax(0, 1fr) auto;
  gap: 20px;
  align-items: start;
  margin-bottom: clamp(34px, 6vw, 66px);
}

.eyebrow,
.count-label {
  margin: 0;
  color: var(--muted);
  font-size: 0.76rem;
  font-weight: 800;
  letter-spacing: 0;
  text-transform: uppercase;
}

.eyebrow {
  margin-bottom: 12px;
}

h1 {
  margin: 0;
  color: var(--ink);
  font-size: clamp(3.4rem, 9vw, 7.5rem);
  font-weight: 900;
  line-height: 0.92;
  letter-spacing: 0;
}

.settings-button,
.close-button,
.primary-button {
  min-height: 44px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: var(--surface);
  color: var(--ink);
  font-weight: 800;
  padding: 0 18px;
  white-space: nowrap;
}

.settings-button:hover,
.close-button:hover {
  border-color: #98a2b3;
  background: var(--surface-soft);
}

.settings-button:focus-visible,
.close-button:focus-visible,
.primary-button:focus-visible,
.format-toggle input:focus-visible + span,
.split-time-field input:focus-visible,
.date-format-field select:focus-visible {
  outline: 3px solid rgba(37, 99, 235, 0.28);
  outline-offset: 2px;
}

.countdown-grid {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 14px;
}

.count-box {
  min-height: 172px;
  display: grid;
  align-content: space-between;
  gap: 20px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: var(--surface);
  padding: clamp(18px, 3vw, 26px);
}

.count-box:nth-child(1) {
  box-shadow: inset 0 4px 0 var(--accent);
}

.count-box:nth-child(2) {
  box-shadow: inset 0 4px 0 var(--teal);
}

.count-box:nth-child(3) {
  box-shadow: inset 0 4px 0 var(--amber);
}

.count-box:nth-child(4) {
  box-shadow: inset 0 4px 0 var(--violet);
}

.count-value {
  display: block;
  color: var(--ink);
  font-size: clamp(2.6rem, 5vw, 5rem);
  font-weight: 900;
  line-height: 0.92;
  letter-spacing: 0;
  font-variant-numeric: tabular-nums;
}

.count-value.milliseconds {
  font-size: clamp(2.25rem, 4.4vw, 4.3rem);
}

.settings-backdrop {
  position: fixed;
  inset: 0;
  z-index: 10;
  background: rgba(16, 24, 40, 0.38);
}

.settings-panel {
  position: fixed;
  top: 18px;
  right: 18px;
  z-index: 11;
  width: min(420px, calc(100vw - 36px));
  max-height: calc(100vh - 36px);
  overflow: auto;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: var(--surface);
  box-shadow: 0 24px 80px rgba(16, 24, 40, 0.22);
  padding: 22px;
}

.settings-header {
  display: flex;
  justify-content: space-between;
  gap: 16px;
  align-items: center;
  margin-bottom: 24px;
}

h2 {
  margin: 0;
  color: var(--ink);
  font-size: 1.45rem;
  line-height: 1.1;
  letter-spacing: 0;
}

.settings-form {
  display: grid;
  gap: 22px;
}

.date-format-field {
  display: grid;
  gap: 8px;
}

.date-format-field span {
  color: var(--muted);
  font-size: 0.78rem;
  font-weight: 800;
  letter-spacing: 0;
  text-transform: uppercase;
}

.date-format-field select {
  width: 100%;
  height: 46px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: var(--surface);
  color: var(--ink);
  font-weight: 800;
  outline: none;
  padding: 0 12px;
}

.date-format-field select:focus {
  border-color: var(--accent);
}

.format-toggle {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 6px;
  width: 100%;
  margin: 0;
  padding: 6px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: var(--surface-soft);
}

.format-toggle legend {
  position: absolute;
  width: 1px;
  height: 1px;
  overflow: hidden;
  clip: rect(0 0 0 0);
}

.format-toggle label {
  min-width: 0;
}

.format-toggle input {
  position: absolute;
  opacity: 0;
  pointer-events: none;
}

.format-toggle span {
  display: grid;
  min-height: 42px;
  place-items: center;
  border-radius: 6px;
  color: var(--muted);
  font-size: 0.92rem;
  font-weight: 800;
}

.format-toggle input:checked + span {
  background: var(--ink);
  color: #ffffff;
}

.split-time-field {
  display: grid;
  grid-template-columns: minmax(0, 1fr) auto minmax(0, 1fr);
  gap: 12px;
  align-items: end;
  width: 100%;
  margin: 0;
  padding: 0;
  border: 0;
}

.split-time-field legend {
  grid-column: 1 / -1;
  color: var(--muted);
  font-size: 0.78rem;
  font-weight: 800;
  letter-spacing: 0;
  text-transform: uppercase;
}

.split-time-field label {
  display: grid;
  gap: 8px;
}

.split-time-field label span {
  color: var(--muted);
  font-size: 0.8rem;
  font-weight: 800;
}

.split-time-field input {
  width: 100%;
  height: 78px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: var(--surface);
  color: var(--ink);
  font-size: clamp(2.2rem, 12vw, 3.4rem);
  font-weight: 900;
  letter-spacing: 0;
  outline: none;
  text-align: center;
  font-variant-numeric: tabular-nums;
}

.split-time-field input:focus {
  border-color: var(--accent);
}

.time-separator {
  display: grid;
  height: 78px;
  place-items: center;
  color: var(--ink);
  font-size: 3rem;
  font-weight: 900;
  line-height: 1;
  font-variant-numeric: tabular-nums;
}

.input-message {
  min-height: 22px;
  margin: 0;
  color: var(--danger);
  font-size: 0.94rem;
  font-weight: 700;
}

.primary-button {
  width: 100%;
  border-color: var(--accent);
  background: var(--accent);
  color: #ffffff;
}

.primary-button:hover {
  background: #1d4ed8;
}

@media (max-width: 760px) {
  .panel-header {
    grid-template-columns: 1fr;
  }

  .settings-button {
    justify-self: start;
  }

  .countdown-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

@media (max-width: 520px) {
  .app-shell {
    padding: 72px 12px;
  }

  .countdown-panel {
    padding: 22px;
  }

  .countdown-grid {
    grid-template-columns: 1fr;
  }

  .count-box {
    min-height: 126px;
  }

  .settings-panel {
    top: 12px;
    right: 12px;
    width: calc(100vw - 24px);
    max-height: calc(100vh - 24px);
  }

  .page-clock {
    top: 12px;
    right: 12px;
  }

  .page-date {
    bottom: 12px;
  }
}