/* ---------- Design tokens (light) ---------- */
:root {
  --color-bg: #eef3f9;
  --color-bg-soft: #f8fbff;
  --color-surface: #ffffff;
  --color-text: #1f2a37;
  --color-text-soft: #526273;
  --color-accent: #2a7a72;
  --color-accent-dark: #1f5c56;
  --color-break: #3b7ea1;
  --color-on-accent: #ffffff;
  --color-paused: #9a6b1e;
  --color-track: #d9e3ee;
  --overlay: rgba(31, 42, 55, 0.35);
  --shadow-card: 0 12px 32px rgba(31, 42, 55, 0.10);
  --radius: 14px;
  --font: "Segoe UI", system-ui, -apple-system, "Helvetica Neue", Arial, sans-serif;
}

/* ---------- Design tokens (dark) ---------- */
[data-theme="dark"] {
  --color-bg: #10161d;
  --color-bg-soft: #17202a;
  --color-surface: #1b2530;
  --color-text: #e8eef5;
  --color-text-soft: #9fb0c1;
  --color-accent: #5fc9bd;
  --color-accent-dark: #8fe0d6;
  --color-break: #6db8dd;
  --color-on-accent: #0e1418;
  --color-paused: #e0b055;
  --color-track: #2c3a48;
  --overlay: rgba(4, 8, 12, 0.6);
  --shadow-card: 0 16px 40px rgba(0, 0, 0, 0.5);
}

/* ---------- Base ---------- */
* { box-sizing: border-box; }

html, body { min-height: 100%; }

body {
  margin: 0;
  padding: 1.5rem 1rem 2rem;
  font-family: var(--font);
  color: var(--color-text);
  background: radial-gradient(circle at 50% 0%, var(--color-bg-soft), var(--color-bg) 70%);
  display: flex;
  justify-content: center;
  align-items: flex-start;
  transition: background-color 0.3s ease, color 0.3s ease;
}

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

/* ---------- Layout ---------- */
.app {
  width: 100%;
  max-width: 34rem;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 1.4rem;
}

.app__header {
  width: 100%;
  display: flex;
  flex-direction: column;
  align-items: center;
  text-align: center;
}

.app__topbar {
  width: 100%;
  display: flex;
  justify-content: flex-end;
  margin-bottom: 0.35rem;
}

/* ---------- Brand / logo ---------- */
.app__brand {
  display: flex;
  align-items: center;
  justify-content: center;
  flex-wrap: wrap;
  gap: 0.6rem;
}

.logo {
  width: 2.4rem;
  height: 2.4rem;
  flex: none;
}

.logo__track {
  fill: none;
  stroke: var(--color-track);
  stroke-width: 5;
}

.logo__arc {
  fill: none;
  stroke: var(--color-accent);
  stroke-width: 5;
  stroke-linecap: round;
  transition: stroke 0.3s ease;
}

/* The mark follows the active mode */
.app.is-break .logo__arc { stroke: var(--color-break); }
.app.is-paused .logo__arc,
.app.is-done .logo__arc { stroke: var(--color-paused); }

.app__title {
  margin: 0;
  font-size: clamp(1.5rem, 5vw, 2rem);
  letter-spacing: -0.01em;
}

.app__subtitle {
  margin: 0.4rem 0 0;
  color: var(--color-text-soft);
  font-size: 0.95rem;
}

/* ---------- Theme toggle ---------- */
.theme-toggle {
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
  font: inherit;
  font-size: 0.8rem;
  font-weight: 600;
  padding: 0.35rem 0.75rem;
  border-radius: 999px;
  border: 1px solid var(--color-track);
  background: var(--color-surface);
  color: var(--color-text-soft);
  cursor: pointer;
  transition: border-color 0.2s ease, color 0.2s ease, background-color 0.2s ease;
}

.theme-toggle:hover {
  border-color: var(--color-accent);
  color: var(--color-accent-dark);
}

/* ---------- Mode switch ---------- */
.modes {
  display: flex;
  gap: 0.25rem;
  padding: 0.25rem;
  border-radius: 999px;
  background: var(--color-surface);
  border: 1px solid var(--color-track);
}

.mode {
  font: inherit;
  font-size: 0.9rem;
  font-weight: 600;
  padding: 0.4rem 1.2rem;
  border: none;
  border-radius: 999px;
  background: transparent;
  color: var(--color-text-soft);
  cursor: pointer;
  transition: background-color 0.2s ease, color 0.2s ease;
}

.mode:hover { color: var(--color-accent-dark); }

.mode[aria-pressed="true"] {
  background: var(--color-accent);
  color: var(--color-on-accent);
}

.mode[aria-pressed="true"][data-mode="break"] {
  background: var(--color-break);
}

[data-theme="dark"] .mode[aria-pressed="true"] { color: var(--color-on-accent); }

/* ---------- Presets ---------- */
.presets { display: flex; justify-content: center; }

.presets__group {
  display: flex;
  gap: 0.5rem;
  flex-wrap: wrap;
  justify-content: center;
}

.presets__group[hidden] { display: none; }

.preset {
  border: 1px solid var(--color-track);
  background: var(--color-surface);
  color: var(--color-text-soft);
  font: inherit;
  font-size: 0.85rem;
  padding: 0.4rem 0.9rem;
  border-radius: 999px;
  cursor: pointer;
  transition: background-color 0.2s ease, color 0.2s ease, border-color 0.2s ease;
}

.preset:hover { border-color: var(--color-accent); color: var(--color-accent-dark); }

.preset[aria-pressed="true"] {
  background: var(--color-accent);
  border-color: var(--color-accent);
  color: var(--color-on-accent);
}

.app.is-break .preset[aria-pressed="true"] {
  background: var(--color-break);
  border-color: var(--color-break);
}

/* ---------- Timer ---------- */
.timer { display: flex; flex-direction: column; align-items: center; gap: 0.75rem; }

.timer__status {
  margin: 0;
  font-size: 0.95rem;
  font-weight: 600;
  letter-spacing: 0.04em;
  text-transform: uppercase;
  color: var(--color-text-soft);
}

.timer__ring {
  position: relative;
  width: min(78vw, 17rem);
  aspect-ratio: 1 / 1;
}

.timer__ring svg {
  width: 100%;
  height: 100%;
  transform: rotate(-90deg);
}

.ring__track,
.ring__progress {
  fill: none;
  stroke-width: 12;
}

.ring__track { stroke: var(--color-track); }

.ring__progress {
  stroke: var(--color-accent);
  stroke-linecap: round;
  transition: stroke-dashoffset 0.2s linear, stroke 0.3s ease;
}

/* Break mode uses a cooler colour */
.app.is-break .ring__progress { stroke: var(--color-break); }

.app.is-paused .ring__progress,
.app.is-done .ring__progress { stroke: var(--color-paused); }

.timer__display {
  position: absolute;
  inset: 0;
  margin: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: clamp(2.5rem, 13vw, 3.75rem);
  font-weight: 700;
  font-variant-numeric: tabular-nums;
}

/* ---------- Buttons ---------- */
.controls {
  display: flex;
  flex-wrap: wrap;
  gap: 0.6rem;
  justify-content: center;
}

.btn {
  font: inherit;
  font-weight: 600;
  padding: 0.7rem 1.4rem;
  border-radius: var(--radius);
  border: 1px solid transparent;
  cursor: pointer;
  transition: background-color 0.2s ease, color 0.2s ease, border-color 0.2s ease, transform 0.1s ease;
}

.btn:active { transform: translateY(1px); }

.btn--primary {
  background: var(--color-accent);
  color: var(--color-on-accent);
}

.btn--primary:hover { background: var(--color-accent-dark); }

.btn--ghost {
  background: var(--color-surface);
  border-color: var(--color-track);
  color: var(--color-text-soft);
}

.btn--ghost:hover { border-color: var(--color-accent); color: var(--color-accent-dark); }

.btn:focus-visible,
.preset:focus-visible,
.mode:focus-visible,
.theme-toggle:focus-visible {
  outline: 3px solid var(--color-accent-dark);
  outline-offset: 2px;
}

/* ---------- Footer ---------- */
.app__footer {
  color: var(--color-text-soft);
  font-size: 0.82rem;
  text-align: center;
  line-height: 1.7;
}

.app__footer p { margin: 0; }

kbd {
  background: var(--color-surface);
  border: 1px solid var(--color-track);
  border-bottom-width: 2px;
  border-radius: 6px;
  padding: 0.05rem 0.35rem;
  font-size: 0.78rem;
  font-family: inherit;
}

/* ---------- Visual notification ---------- */
.notice {
  position: fixed;
  inset: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 1rem;
  background: var(--overlay);
  backdrop-filter: blur(4px);
  opacity: 0;
  transition: opacity 0.35s ease;
  z-index: 10;
}

.notice[hidden] { display: none; }
.notice.is-visible { opacity: 1; }

.notice__card {
  background: var(--color-surface);
  color: var(--color-text);
  border-radius: 20px;
  box-shadow: var(--shadow-card);
  padding: 2rem 1.75rem;
  max-width: 22rem;
  text-align: center;
  transform: translateY(12px) scale(0.98);
  transition: transform 0.35s ease;
}

.notice.is-visible .notice__card { transform: translateY(0) scale(1); }

.notice__emoji { margin: 0; font-size: 2.25rem; }
.notice__title { margin: 0.5rem 0 0; font-size: 1.35rem; }
.notice__text { margin: 0.5rem 0 1.25rem; color: var(--color-text-soft); }

/* ---------- Smaller screens ---------- */
@media (max-width: 380px) {
  .btn { padding: 0.65rem 1rem; font-size: 0.9rem; }
  .mode { padding: 0.4rem 0.9rem; }
  .logo { width: 2rem; height: 2rem; }
}

/* ---------- Reduced motion ---------- */
@media (prefers-reduced-motion: reduce) {
  * { transition-duration: 0.01ms !important; }
}