:root {
  --bg: #0a0f11;
  --bg-glow: #102b29;
  --surface: #161f22;
  --surface-border: rgba(255, 255, 255, 0.07);
  --teal: #2af0c9;
  --teal-soft: #1b8f80;
  --teal-dark: #123c3a;
  --orange: #ffab2e;
  --red: #ff5a6a;
  --orange-glow: rgba(255, 171, 46, 0.3);
  --red-glow: rgba(255, 90, 106, 0.3);
  --track: #212d30;
  --text: #eef5f4;
  --text-muted: #82918f;
  --danger-dark: #1c1416;

  /* --- Sizing tokens (overridden by the responsive breakpoints below) --- */
  --app-padding-y: 24px;
  --app-padding-x: 44px;
  --side-col-width: 220px;
  --panel-gap: 24px;
  --font-workout-title: 16px;

  --font-stat-label: 17px;
  --font-stat-value: 30px;

  --font-upcoming-label: 16px;
  --font-upcoming-title: 27px;

  --cadence-padding: 16px 26px 24px;
  --cadence-margin-bottom: 22px;
  --font-phase-label: 27px;
  --bar-height: 20px;
  --thumb-size: 34px;

  --gauge-max-width: 600px;
  --font-stage-count: 19px;
  --font-action-label: 42px;
  --font-stage-timer: 66px;
  --font-stage-name: 21px;
  --font-countdown-number: 110px;

  --font-spm-value: 54px;
  --font-spm-label: 17px;
  --ctrl-btn-size: 66px;
  --ctrl-gap: 15px;
}

* { box-sizing: border-box; }

html, body {
  margin: 0;
  padding: 0;
  height: 100%;
  background: radial-gradient(ellipse 900px 500px at 50% -8%, var(--bg-glow) 0%, var(--bg) 60%) var(--bg);
  color: var(--text);
  font-family: "Segoe UI", Arial, sans-serif;
  user-select: none;
  overflow: hidden;
  overscroll-behavior: none;
  touch-action: manipulation;
}

.app {
  position: relative;
  display: grid;
  grid-template-columns: var(--side-col-width) 1fr var(--side-col-width);
  align-items: center;
  height: 100vh;
  height: 100dvh;
  padding-top: max(var(--app-padding-y), env(safe-area-inset-top));
  padding-bottom: max(var(--app-padding-y), env(safe-area-inset-bottom));
  padding-left: max(var(--app-padding-x), env(safe-area-inset-left));
  padding-right: max(var(--app-padding-x), env(safe-area-inset-right));
}

.top-controls {
  position: absolute;
  top: 22px;
  right: var(--app-padding-x);
  display: flex;
  align-items: center;
  gap: 8px;
  z-index: 5;
}

.top-control-btn,
.settings-btn {
  background: transparent;
  border: none;
  color: var(--text-muted);
  cursor: pointer;
  padding: 6px;
}
.top-control-btn:hover,
.settings-btn:hover {
  color: var(--teal);
}
.top-control-btn.off {
  opacity: 0.35;
}

.rotate-banner {
  position: fixed;
  top: env(safe-area-inset-top, 0px);
  left: 50%;
  transform: translateX(-50%);
  z-index: 30;
  display: flex;
  align-items: center;
  gap: 10px;
  margin-top: 10px;
  padding: 10px 14px;
  background: var(--surface);
  border: 1px solid var(--surface-border);
  border-radius: 999px;
  box-shadow: 0 10px 30px -10px rgba(0, 0, 0, 0.6);
  color: var(--text);
  font-size: 14px;
  font-weight: 600;
  white-space: nowrap;
}
.rotate-banner[hidden] {
  display: none;
}
.rotate-banner svg {
  flex-shrink: 0;
  color: var(--teal);
}
.rotate-banner button {
  background: none;
  border: none;
  color: var(--text-muted);
  font-size: 20px;
  line-height: 1;
  cursor: pointer;
  padding: 0 0 0 4px;
}
.rotate-banner button:hover {
  color: var(--text);
}

.workout-title {
  position: absolute;
  top: 22px;
  left: 50%;
  transform: translateX(-50%);
  max-width: min(60%, 480px);
  font-size: var(--font-workout-title);
  font-weight: 700;
  color: var(--text-muted);
  text-align: center;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.left-panel {
  display: flex;
  flex-direction: column;
  gap: var(--panel-gap);
  justify-self: start;
}

.stat-label {
  font-size: var(--font-stat-label);
  color: var(--text-muted);
}

.stat-value {
  font-size: var(--font-stat-value);
  font-weight: 800;
  letter-spacing: 0.5px;
  color: var(--text);
}

.center-panel {
  display: flex;
  flex-direction: column;
  align-items: center;
  text-align: center;
}

.upcoming-label {
  font-size: var(--font-upcoming-label);
  color: var(--text-muted);
  margin-bottom: 4px;
}

.upcoming-title {
  font-size: var(--font-upcoming-title);
  font-weight: 800;
  margin-bottom: 8px;
  min-height: 1.2em;
  color: var(--text);
}

.cadence-panel {
  width: min(560px, 92%);
  background: var(--surface);
  border: 1px solid var(--surface-border);
  border-radius: 20px;
  padding: var(--cadence-padding);
  margin-bottom: var(--cadence-margin-bottom);
  box-shadow: 0 0 0 1px rgba(0, 0, 0, 0.2), 0 10px 30px -12px rgba(0, 0, 0, 0.6);
  transition: box-shadow 0.15s ease;
}
.cadence-panel[hidden] {
  display: none;
}

.phase-label {
  font-size: var(--font-phase-label);
  font-weight: 900;
  letter-spacing: 2px;
  min-height: 1.2em;
  margin-bottom: 10px;
  color: var(--text-muted);
  transition: color 0.1s linear;
}
.phase-label.drive { color: var(--red); }
.phase-label.recover { color: var(--orange); }

.stroke-bar-track {
  position: relative;
  width: 100%;
  height: var(--bar-height);
  border-radius: 999px;
  background: var(--track);
}
.stroke-bar-fill {
  position: absolute;
  inset: 0;
  width: 0%;
  border-radius: 999px;
  background: var(--orange);
}
.stroke-bar-thumb {
  position: absolute;
  top: 50%;
  left: 0%;
  width: var(--thumb-size);
  height: var(--thumb-size);
  border-radius: 50%;
  background: var(--surface);
  border: 5px solid var(--orange);
  transform: translate(-50%, -50%);
  box-shadow: 0 2px 10px rgba(0, 0, 0, 0.5);
}

.gauge-wrap {
  position: relative;
  width: 100%;
  max-width: var(--gauge-max-width);
}

#gauge {
  width: 100%;
  height: auto;
  display: block;
}

.arc {
  fill: none;
  stroke-linecap: round;
}
.arc-bg { stroke: var(--track); stroke-width: 22; }
#arc-progress {
  stroke: var(--teal);
  stroke-width: 22;
  filter: drop-shadow(0 0 6px rgba(42, 240, 201, 0.45));
}

.gauge-center {
  position: absolute;
  left: 50%;
  top: 62%;
  transform: translate(-50%, -50%);
  text-align: center;
  width: 100%;
}

.countdown-overlay {
  position: absolute;
  inset: 0;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  background: rgba(10, 15, 17, 0.94);
  border-radius: 24px;
}
.countdown-overlay[hidden] {
  display: none;
}
.countdown-label {
  font-size: 19px;
  font-weight: 700;
  color: var(--text-muted);
  margin-bottom: 6px;
}
.countdown-number {
  font-size: var(--font-countdown-number);
  font-weight: 900;
  line-height: 1;
  color: var(--teal);
  text-shadow: 0 0 30px rgba(42, 240, 201, 0.35);
}

.stage-count {
  font-size: var(--font-stage-count);
  color: var(--text-muted);
  font-weight: 600;
}

.action-label {
  font-size: var(--font-action-label);
  font-weight: 900;
  color: var(--teal);
  line-height: 1.1;
}
.action-label.paused {
  color: var(--text-muted);
}

.stage-timer {
  font-size: var(--font-stage-timer);
  font-weight: 900;
  letter-spacing: 2px;
  color: var(--text);
  text-shadow: 0 0 24px rgba(42, 240, 201, 0.25);
  transition: color 0.15s ease;
}
.stage-timer.ending {
  color: var(--orange);
  text-shadow: 0 0 24px rgba(255, 171, 46, 0.35);
}

.stage-name {
  font-size: var(--font-stage-name);
  font-weight: 800;
  text-transform: uppercase;
  letter-spacing: 1px;
  margin-top: 2px;
  color: var(--text-muted);
}

.right-panel {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: var(--panel-gap);
  justify-self: end;
}

.spm-display {
  text-align: center;
}
.spm-value {
  font-size: var(--font-spm-value);
  font-weight: 900;
  line-height: 1;
  color: var(--text);
}
.spm-label {
  font-size: var(--font-spm-label);
  font-weight: 700;
  color: var(--teal);
  margin-top: 4px;
}

.controls {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--ctrl-gap);
}

.ctrl-btn {
  width: var(--ctrl-btn-size);
  height: var(--ctrl-btn-size);
  border-radius: 50%;
  border: none;
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  color: var(--text);
}
.ctrl-secondary { background: var(--teal-dark); }
.ctrl-dark { background: var(--danger-dark); color: var(--text-muted); }
.ctrl-primary {
  background: var(--teal);
  color: #052422;
  box-shadow: 0 0 22px rgba(42, 240, 201, 0.4);
}
.ctrl-btn:active { filter: brightness(0.85); }

.settings-panel {
  position: fixed;
  inset: 0;
  background: rgba(0, 0, 0, 0.6);
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 20;
}
.settings-panel[hidden] {
  display: none;
}
.settings-inner {
  background: var(--surface);
  border: 1px solid var(--surface-border);
  border-radius: 12px;
  padding: 28px 32px;
  width: 360px;
  max-width: 90vw;
  box-shadow: 0 20px 60px rgba(0, 0, 0, 0.6);
}
.settings-inner h2 { margin: 0 0 12px; font-size: 20px; color: var(--text); }
.workout-name { color: var(--text-muted); margin-bottom: 18px; }

.select-label {
  display: block;
  font-size: 13px;
  font-weight: 700;
  color: var(--text-muted);
  margin-bottom: 6px;
}
.workout-select {
  display: block;
  width: 100%;
  background: var(--bg);
  border: 1px solid var(--surface-border);
  color: var(--text);
  padding: 11px 12px;
  border-radius: 8px;
  margin-bottom: 16px;
  font-size: 15px;
  cursor: pointer;
}
.workout-select:hover,
.workout-select:focus {
  border-color: var(--teal);
  outline: none;
}

.file-label {
  display: block;
  background: var(--teal);
  color: #052422;
  text-align: center;
  padding: 12px;
  border-radius: 8px;
  cursor: pointer;
  margin-bottom: 12px;
  font-weight: 700;
}
.file-label input { display: none; }
.text-btn {
  display: block;
  width: 100%;
  background: none;
  border: 1px solid var(--surface-border);
  color: var(--text);
  padding: 10px;
  border-radius: 8px;
  margin-top: 8px;
  cursor: pointer;
  font-size: 15px;
}
.text-btn:hover { border-color: var(--teal); color: var(--teal); }

/* Portrait phones/tablets: plenty of height, so stack the three columns.
   The four control buttons go in a single row (there's width to spare) and
   grow a bit, since this is the layout used for actual thumb-tapping. */
@media (max-width: 900px) and (min-height: 560px) {
  :root {
    --ctrl-btn-size: 78px;
    --ctrl-gap: 14px;
  }
  .app {
    grid-template-columns: 1fr;
    grid-template-rows: auto auto auto;
    justify-items: center;
    height: auto;
    min-height: 100vh;
    gap: 24px;
    padding: 60px 20px 30px;
  }
  .left-panel { flex-direction: row; flex-wrap: wrap; justify-content: center; gap: 10px 26px; max-width: 90vw; }
  .right-panel { flex-direction: column; }
  .controls { grid-template-columns: repeat(4, 1fr); }
}

/* Landscape phones (short viewport): keep the 3-column layout - it already
   fits the width - but scale everything down so it fits the height without
   scrolling. Re-declares the grid explicitly so it always wins here even if
   the width also happens to match the portrait-stacking query above. */
@media (max-height: 500px) {
  :root {
    --app-padding-y: 8px;
    --app-padding-x: 18px;
    --side-col-width: 130px;
    --panel-gap: 8px;
    --font-workout-title: 11px;

    --font-stat-label: 11px;
    --font-stat-value: 17px;

    --font-upcoming-label: 11px;
    --font-upcoming-title: 15px;

    --cadence-padding: 6px 14px 10px;
    --cadence-margin-bottom: 8px;
    --font-phase-label: 15px;
    --bar-height: 10px;
    --thumb-size: 20px;

    --gauge-max-width: 280px;
    --font-stage-count: 12px;
    --font-action-label: 20px;
    --font-stage-timer: 32px;
    --font-stage-name: 12px;
    --font-countdown-number: 56px;

    --font-spm-value: 24px;
    --font-spm-label: 10px;
    --ctrl-btn-size: 46px;
    --ctrl-gap: 6px;
  }

  .app {
    grid-template-columns: var(--side-col-width) 1fr var(--side-col-width);
    grid-template-rows: none;
    height: 100vh;
    min-height: 0;
  }
  .left-panel { flex-direction: column; }
  .right-panel { flex-direction: row-reverse; align-items: center; }
  .right-panel .spm-display { margin-right: 8px; }
  .controls { grid-template-columns: 1fr; }
  .top-controls { top: 6px; }
  .workout-title { top: 6px; }
  .ctrl-btn svg { width: 60%; height: 60%; }
  .stage-timer { text-shadow: none; }
  .action-label { line-height: 1; }
}