/* ===== Reset & Base ===== */
*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

:root {
  --clr-work: #f97316;
  --clr-work-glow: rgba(249, 115, 22, 0.35);
  --clr-break: #06b6d4;
  --clr-break-glow: rgba(6, 182, 212, 0.35);
  --clr-accent: var(--clr-work);
  --clr-accent-glow: var(--clr-work-glow);
  --bg: #080c14;
  --surface: rgba(255, 255, 255, 0.04);
  --surface-border: rgba(255, 255, 255, 0.08);
  --text-primary: #f1f5f9;
  --text-muted: #64748b;
  --ring-track: rgba(255, 255, 255, 0.07);
  --transition-phase: color 0.6s ease, stroke 0.6s ease, box-shadow 0.6s ease;
}

[data-phase="work"] {
  --clr-accent: var(--clr-work);
  --clr-accent-glow: var(--clr-work-glow);
}

[data-phase="break"] {
  --clr-accent: var(--clr-break);
  --clr-accent-glow: var(--clr-break-glow);
}

body {
  font-family: 'Segoe UI', system-ui, sans-serif;
  background: var(--bg);
  background-image: radial-gradient(ellipse 80% 60% at 50% 0%, rgba(249,115,22,0.06) 0%, transparent 70%);
  color: var(--text-primary);
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  align-items: center;
  padding: 32px 16px 64px;
  transition: background-image 0.6s ease;
}

[data-phase="break"] body,
[data-phase="break"] {
  background-image: radial-gradient(ellipse 80% 60% at 50% 0%, rgba(6,182,212,0.06) 0%, transparent 70%);
}

/* ===== Back Link ===== */
.back-link {
  align-self: flex-start;
  color: var(--text-muted);
  text-decoration: none;
  font-size: 0.85rem;
  letter-spacing: 0.02em;
  transition: color 0.2s;
  margin-bottom: 32px;
}

.back-link:hover {
  color: var(--text-primary);
}

/* ===== Layout ===== */
main {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 20px;
  width: 100%;
  max-width: 620px;
}

/* ===== App Title ===== */
.app-title {
  font-size: 1.3rem;
  font-weight: 600;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--text-muted);
}

/* ===== Timer Card ===== */
.timer-card {
  width: 100%;
  background: var(--surface);
  border: 1px solid var(--surface-border);
  border-radius: 24px;
  padding: 48px 40px 44px;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 32px;
  backdrop-filter: blur(12px);
}

/* ===== Status Label ===== */
.status-label {
  font-size: 0.95rem;
  font-weight: 700;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--clr-accent);
  height: 1em;
  transition: var(--transition-phase);
}

/* ===== Ring ===== */
.ring-wrap {
  position: relative;
  width: 288px;
  height: 288px;
}

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

.ring-track {
  fill: none;
  stroke: var(--ring-track);
  stroke-width: 10;
}

.ring-progress {
  fill: none;
  stroke: var(--clr-accent);
  stroke-width: 10;
  stroke-linecap: round;
  /* circumference = 2 * π * 128 ≈ 804.25 */
  stroke-dasharray: 804.25;
  stroke-dashoffset: 0;
  filter: drop-shadow(0 0 8px var(--clr-accent-glow));
  transition: stroke-dashoffset 1s linear, stroke 0.6s ease, filter 0.6s ease;
}

.ring-inner {
  position: absolute;
  inset: 0;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 6px;
}

/* ===== Phase & Time ===== */
.phase-label {
  font-size: 0.9rem;
  font-weight: 600;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--clr-accent);
  transition: var(--transition-phase);
}

.time-display {
  font-size: 4.4rem;
  font-weight: 700;
  font-variant-numeric: tabular-nums;
  letter-spacing: 0.04em;
  color: var(--text-primary);
  text-shadow: 0 0 32px var(--clr-accent-glow);
  transition: text-shadow 0.6s ease;
  line-height: 1;
}

/* ===== Buttons ===== */
.btn-row {
  display: flex;
  gap: 12px;
  width: 100%;
}

.btn {
  flex: 1;
  padding: 17px;
  border: none;
  border-radius: 12px;
  font-size: 1.1rem;
  font-weight: 600;
  letter-spacing: 0.04em;
  cursor: pointer;
  transition: opacity 0.15s, transform 0.1s, background 0.6s ease, box-shadow 0.6s ease;
}

.btn:active {
  transform: scale(0.97);
}

.btn-primary {
  background: var(--clr-accent);
  color: #0a0a0a;
  box-shadow: 0 4px 20px var(--clr-accent-glow);
}

.btn-primary:hover {
  opacity: 0.88;
}

.btn-secondary {
  background: rgba(255, 255, 255, 0.07);
  color: var(--text-muted);
  border: 1px solid var(--surface-border);
}

.btn-secondary:hover {
  background: rgba(255, 255, 255, 0.12);
  color: var(--text-primary);
}

/* ===== Settings Card ===== */
.settings-card {
  width: 100%;
  background: var(--surface);
  border: 1px solid var(--surface-border);
  border-radius: 20px;
  padding: 28px 32px;
  backdrop-filter: blur(12px);
}

.settings-heading {
  font-size: 1rem;
  font-weight: 700;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--text-muted);
  margin-bottom: 18px;
}

.settings-grid {
  display: flex;
  align-items: center;
  gap: 0;
}

.setting-group {
  flex: 1;
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.setting-divider {
  width: 1px;
  height: 56px;
  background: var(--surface-border);
  margin: 0 20px;
  flex-shrink: 0;
}

.setting-label {
  font-size: 1.1rem;
  color: var(--text-muted);
  font-weight: 500;
}

.time-inputs {
  display: flex;
  gap: 10px;
}

.input-unit {
  display: flex;
  align-items: center;
  gap: 6px;
  font-size: 1.1rem;
  color: var(--text-muted);
  cursor: default;
}

.input-unit input {
  width: 72px;
  padding: 9px 10px;
  background: rgba(255, 255, 255, 0.06);
  border: 1px solid var(--surface-border);
  border-radius: 8px;
  color: var(--text-primary);
  font-size: 1.2rem;
  font-weight: 600;
  text-align: center;
  outline: none;
  transition: border-color 0.2s, box-shadow 0.2s;
  /* hide spinner arrows */
  -moz-appearance: textfield;
}

.input-unit input::-webkit-inner-spin-button,
.input-unit input::-webkit-outer-spin-button {
  -webkit-appearance: none;
}

.input-unit input:focus {
  border-color: var(--clr-accent);
  box-shadow: 0 0 0 3px var(--clr-accent-glow);
}