:root {
  color-scheme: light dark;
  --bg: #fff7f2;
  --surface: rgba(255, 253, 249, 0.82);
  --surface-strong: #fffdf9;
  --surface-muted: rgba(255, 246, 240, 0.9);
  --text: #231815;
  --muted: #6f625d;
  --border: rgba(123, 95, 86, 0.14);
  --primary: #e74c3c;
  --success: #2ecc71;
  --danger: #e53935;
  --ring: #ff6b6b;
  --shadow: 0 24px 70px rgba(110, 59, 42, 0.12);
  --shadow-hover: 0 18px 36px rgba(110, 59, 42, 0.16);
  --focus-ring: 0 0 0 3px rgba(255, 107, 107, 0.3);
  --font-body: "Noto Sans SC", "PingFang SC", "Hiragino Sans GB",
    "Microsoft YaHei", "ui-rounded", system-ui, -apple-system, "Segoe UI", Roboto,
    Inter, sans-serif;
  --font-mono: "SFMono-Regular", ui-monospace, "Cascadia Mono", "Segoe UI Mono",
    monospace;
  --step--1: 0.888rem;
  --step-0: 1rem;
  --step-1: 1.125rem;
  --step-2: 1.423rem;
  --step-3: 1.802rem;
  --step-4: 2.488rem;
  --step-5: 4.209rem;
  --sp-4: 4px;
  --sp-8: 8px;
  --sp-12: 12px;
  --sp-16: 16px;
  --sp-24: 24px;
  --sp-32: 32px;
  --r-8: 8px;
  --r-12: 12px;
  --r-16: 16px;
  --r-24: 24px;
  --ease: cubic-bezier(0.2, 0.8, 0.2, 1);
  --dur-200: 200ms;
  --phase-accent: var(--primary);
  --phase-soft: rgba(231, 76, 60, 0.12);
  --phase-contrast: #fff7f2;
}

body[data-theme="dark"] {
  --bg: #171413;
  --surface: rgba(30, 26, 24, 0.82);
  --surface-strong: #211c1a;
  --surface-muted: rgba(46, 38, 35, 0.85);
  --text: #f8efe8;
  --muted: #c3b1a7;
  --border: rgba(255, 239, 229, 0.08);
  --shadow: 0 30px 80px rgba(0, 0, 0, 0.36);
  --shadow-hover: 0 22px 48px rgba(0, 0, 0, 0.42);
  --focus-ring: 0 0 0 3px rgba(255, 107, 107, 0.35);
}

body[data-phase="focus"] {
  --phase-accent: var(--primary);
  --phase-soft: rgba(231, 76, 60, 0.14);
  --phase-contrast: #ffffff;
}

body[data-phase="shortBreak"] {
  --phase-accent: #5b9f6f;
  --phase-soft: rgba(91, 159, 111, 0.16);
  --phase-contrast: #f6fff8;
}

body[data-phase="longBreak"] {
  --phase-accent: #3f7b8f;
  --phase-soft: rgba(63, 123, 143, 0.16);
  --phase-contrast: #f4fbff;
}

* {
  box-sizing: border-box;
}

html {
  font-size: 16px;
}

body {
  margin: 0;
  min-height: 100vh;
  font-family: var(--font-body);
  color: var(--text);
  background:
    radial-gradient(circle at top left, rgba(231, 76, 60, 0.12), transparent 32%),
    radial-gradient(circle at right 18% top 18%, rgba(46, 204, 113, 0.1), transparent 24%),
    linear-gradient(180deg, rgba(255, 255, 255, 0.4), transparent 24%),
    var(--bg);
  transition:
    background-color var(--dur-200) var(--ease),
    color var(--dur-200) var(--ease);
}

button,
input,
summary {
  font: inherit;
}

button,
input {
  color: inherit;
}

button {
  border: 0;
  cursor: pointer;
}

button:focus-visible,
input:focus-visible,
summary:focus-visible {
  outline: none;
  box-shadow: var(--focus-ring);
}

.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}

.page-glow {
  position: fixed;
  inset: auto;
  width: 18rem;
  height: 18rem;
  border-radius: 999px;
  filter: blur(24px);
  opacity: 0.32;
  pointer-events: none;
  z-index: 0;
}

.page-glow-a {
  top: 4%;
  right: 8%;
  background: rgba(231, 76, 60, 0.22);
}

.page-glow-b {
  left: 4%;
  bottom: 12%;
  background: rgba(46, 204, 113, 0.18);
}

.app-shell {
  position: relative;
  z-index: 1;
  width: min(1200px, calc(100% - 32px));
  margin: 0 auto;
  padding: 32px 0 48px;
}

.app-header {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: 20px;
  margin-bottom: 24px;
}

.eyebrow {
  margin: 0 0 8px;
  color: var(--muted);
  font-size: var(--step--1);
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.app-header h1,
.timer-card h2,
.settings-panel h2,
.section-heading h3 {
  margin: 0;
}

.app-header h1 {
  font-size: clamp(2rem, 3vw, 2.8rem);
  line-height: 1;
}

.header-copy {
  margin: 10px 0 0;
  max-width: 32ch;
  color: var(--muted);
}

.layout-grid {
  display: grid;
  grid-template-columns: minmax(0, 1.2fr) minmax(320px, 0.8fr);
  gap: 24px;
  align-items: start;
}

.card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 28px;
  box-shadow: var(--shadow);
  backdrop-filter: blur(18px);
}

.timer-card {
  padding: 28px;
}

.timer-card-top {
  display: flex;
  justify-content: space-between;
  gap: 20px;
  align-items: start;
}

.timer-card h2 {
  font-size: var(--step-2);
}

.segmented-control {
  display: inline-flex;
  gap: 6px;
  padding: 6px;
  background: var(--surface-muted);
  border: 1px solid var(--border);
  border-radius: 999px;
}

.theme-option,
.phase-pill {
  border-radius: 999px;
  padding: 10px 14px;
  min-height: 44px;
  font-size: 0.94rem;
  transition:
    transform var(--dur-200) var(--ease),
    background-color var(--dur-200) var(--ease),
    color var(--dur-200) var(--ease),
    box-shadow var(--dur-200) var(--ease);
}

.theme-option {
  background: transparent;
}

.theme-option:hover,
.primary-action:hover,
.secondary-action:hover {
  transform: translateY(-1px);
  box-shadow: var(--shadow-hover);
}

.theme-option.is-active {
  background: var(--surface-strong);
  box-shadow: inset 0 0 0 1px var(--border);
}

.phase-pill {
  color: var(--muted);
}

.phase-pill.is-active {
  background: var(--phase-accent);
  color: var(--phase-contrast);
}

.timer-visual {
  position: relative;
  display: grid;
  place-items: center;
  margin: 24px 0 20px;
  padding: 20px 0 8px;
}

.progress-ring {
  width: min(100%, 420px);
  aspect-ratio: 1;
  overflow: visible;
}

.ring-track,
.ring-progress {
  fill: none;
  stroke-width: 16;
  transform: rotate(-90deg);
  transform-origin: 50% 50%;
}

.ring-track {
  stroke: rgba(127, 92, 79, 0.12);
}

body[data-theme="dark"] .ring-track {
  stroke: rgba(255, 239, 229, 0.12);
}

.ring-progress {
  stroke: var(--phase-accent);
  transition: stroke var(--dur-200) var(--ease);
  filter: drop-shadow(0 8px 18px color-mix(in srgb, var(--phase-accent) 28%, transparent));
}

.timer-readout {
  position: absolute;
  display: grid;
  justify-items: center;
  gap: 10px;
}

.phase-badge {
  margin: 0;
  padding: 8px 14px;
  border-radius: 999px;
  background: var(--phase-soft);
  color: var(--phase-accent);
  font-size: 0.95rem;
  font-weight: 700;
}

.time-display {
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  font-size: clamp(3.8rem, 9vw, 6.6rem);
  line-height: 0.95;
  letter-spacing: -0.06em;
}

.supporting-copy {
  margin: 0;
  color: var(--muted);
}

.controls {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 12px;
}

.primary-action,
.secondary-action {
  min-height: 52px;
  padding: 12px 18px;
  border-radius: 18px;
  transition:
    transform var(--dur-200) var(--ease),
    box-shadow var(--dur-200) var(--ease),
    background-color var(--dur-200) var(--ease),
    color var(--dur-200) var(--ease),
    opacity var(--dur-200) var(--ease);
}

.primary-action {
  background: linear-gradient(135deg, var(--primary), #ff7b66);
  color: white;
}

.primary-action.is-paused,
.primary-action.is-running {
  background: linear-gradient(135deg, var(--phase-accent), color-mix(in srgb, var(--phase-accent) 70%, white));
}

.secondary-action {
  background: var(--surface-strong);
  color: var(--text);
  box-shadow: inset 0 0 0 1px var(--border);
}

.success-action {
  background: linear-gradient(135deg, var(--success), #8bc46a);
  color: #fff;
  box-shadow: none;
}

.primary-action:active,
.secondary-action:active,
.theme-option:active {
  transform: translateY(1px);
}

.primary-action:disabled,
.secondary-action:disabled {
  opacity: 0.48;
  cursor: not-allowed;
  box-shadow: none;
  transform: none;
}

.status-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 12px;
  margin-top: 18px;
}

.status-card {
  padding: 16px;
  border-radius: 20px;
  background: var(--surface-muted);
  border: 1px solid var(--border);
}

.status-label,
.status-note,
.status-shortcuts {
  margin: 0;
}

.status-label,
.status-note {
  color: var(--muted);
}

.status-value {
  margin: 6px 0;
  font-size: var(--step-3);
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
}

.status-shortcuts + .status-shortcuts {
  margin-top: 6px;
}

.settings-column {
  position: sticky;
  top: 20px;
}

.settings-panel {
  overflow: hidden;
}

.settings-panel summary {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  padding: 24px 24px 16px;
  list-style: none;
  cursor: pointer;
}

.settings-panel summary::-webkit-details-marker {
  display: none;
}

.summary-hint {
  color: var(--muted);
  font-size: var(--step--1);
}

#settingsForm {
  display: grid;
  gap: 20px;
  padding: 0 24px 24px;
}

.settings-section {
  display: grid;
  gap: 14px;
  padding-top: 16px;
  border-top: 1px solid var(--border);
}

.section-heading p,
.helper-text,
.error-text {
  margin: 6px 0 0;
  color: var(--muted);
  font-size: var(--step--1);
}

.field,
.toggle-row {
  display: grid;
  gap: 10px;
}

.input-with-suffix,
.slider-row {
  display: flex;
  align-items: center;
  gap: 12px;
}

.input-with-suffix {
  min-height: 48px;
  padding: 6px 12px;
  border: 1px solid var(--border);
  border-radius: 16px;
  background: var(--surface-strong);
}

.input-with-suffix input {
  width: 100%;
  border: 0;
  background: transparent;
  min-height: 36px;
  padding: 0;
  outline: none;
}

.input-with-suffix span,
#volumeValue {
  color: var(--muted);
  white-space: nowrap;
}

.toggle-row {
  grid-template-columns: 1fr auto;
  align-items: center;
  min-height: 48px;
  padding: 6px 0;
}

input[type="checkbox"] {
  appearance: none;
  width: 52px;
  height: 32px;
  border-radius: 999px;
  background: rgba(132, 117, 110, 0.24);
  position: relative;
  transition: background-color var(--dur-200) var(--ease);
}

input[type="checkbox"]::after {
  content: "";
  position: absolute;
  top: 4px;
  left: 4px;
  width: 24px;
  height: 24px;
  border-radius: 50%;
  background: white;
  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.15);
  transition: transform var(--dur-200) var(--ease);
}

input[type="checkbox"]:checked {
  background: var(--phase-accent);
}

input[type="checkbox"]:checked::after {
  transform: translateX(20px);
}

input[type="range"] {
  width: 100%;
  accent-color: var(--phase-accent);
}

.settings-actions {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 12px;
}

.error-text {
  min-height: 1.2em;
  color: var(--danger);
}

.input-invalid {
  box-shadow: inset 0 0 0 1px var(--danger);
}

@media (max-width: 1023px) {
  .layout-grid {
    grid-template-columns: 1fr;
  }

  .settings-column {
    position: static;
  }
}

@media (max-width: 768px) {
  .app-shell {
    width: min(100% - 24px, 960px);
    padding-top: 20px;
  }

  .app-header,
  .timer-card-top {
    flex-direction: column;
  }

  .timer-card,
  .settings-panel summary,
  #settingsForm {
    padding-left: 18px;
    padding-right: 18px;
  }

  #settingsForm {
    padding-bottom: 18px;
  }

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

@media (max-width: 480px) {
  .theme-switcher,
  .phase-indicator {
    width: 100%;
    justify-content: space-between;
  }

  .theme-option,
  .phase-pill {
    flex: 1;
    text-align: center;
    padding-inline: 10px;
    min-width: 0;
  }

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

  .controls > :first-child {
    grid-column: 1 / -1;
  }

  .time-display {
    font-size: clamp(3.2rem, 20vw, 5rem);
  }

  .timer-card {
    padding: 18px;
  }

  .settings-panel summary {
    align-items: start;
  }

  .summary-hint {
    padding-top: 4px;
  }
}

@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    scroll-behavior: auto !important;
    transition-duration: 0.01ms !important;
  }
}