/* 1. Design tokens */
:root {
  --paper: #F7F8FA;
  --surface: #FFFFFF;

  --ink: #202B3C;
  --muted: #758093;
  --line: #E5E9EF;

  --hy-blue: #174F85;
  --blue: #174F85;
  --blue-soft: #EDF3F9;

  --free: #2469A6;
  --free-soft: #EDF3F9;

  --ended: #7D8795;
  --ended-soft: #F0F2F5;

  --now: #D84B4B;

  box-sizing: border-box;
  padding-top: env(safe-area-inset-top, 0px);
  padding-bottom: env(safe-area-inset-bottom, 0px);
}

@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) {
    --paper: #151922;
    --surface: #1D232E;
    --ink: #EDF1F7;
    --muted: #9BA6B7;
    --line: #303847;

    --hy-blue: #79A9D7;
    --blue: #79A9D7;
    --blue-soft: #26364A;

    --free: #8CB9E4;
    --free-soft: #26364A;

    --ended: #A0A9B6;
    --ended-soft: #2A303A;

    --now: #F07878;
  }
}

:root[data-theme="dark"] {
  --paper: #151922;
  --surface: #1D232E;
  --ink: #EDF1F7;
  --muted: #9BA6B7;
  --line: #303847;

  --hy-blue: #79A9D7;
  --blue: #79A9D7;
  --blue-soft: #26364A;

  --free: #8CB9E4;
  --free-soft: #26364A;

  --ended: #A0A9B6;
  --ended-soft: #2A303A;

  --now: #F07878;
}

*, *::before, *::after {
  box-sizing: inherit;
}

html {
  scroll-padding-top: env(safe-area-inset-top, 0px);
  -webkit-text-size-adjust: 100%;
}

body {
  margin: 0;
  background: var(--paper);
  color: var(--ink);

  font-family:
    -apple-system,
    BlinkMacSystemFont,
    "Apple SD Gothic Neo",
    "Malgun Gothic",
    "Noto Sans KR",
    sans-serif;

  font-size: 15px;
  line-height: 1.55;
  letter-spacing: -0.025em;
  -webkit-font-smoothing: antialiased;
}

button, input, select, textarea {
  font: inherit;
  color: inherit;
  letter-spacing: inherit;
}

button {
  cursor: pointer;
  -webkit-tap-highlight-color: transparent;
}

:focus-visible {
  outline: 2px solid var(--blue);
  outline-offset: 3px;
}

.wrap {
  max-width: 560px;
  margin: 0 auto;
  padding: 0 18px 104px;
}

/* 2. Header & clock */

.clock {
  position: sticky;
  top: env(safe-area-inset-top, 0px);
  z-index: 5;

  background: var(--paper);
  padding: 16px 0 14px;
  margin-bottom: 20px;

  border-bottom: 1px solid var(--line);
}

.clock-row {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
}

.brand {
  font-size: 19px;
  font-weight: 750;
  letter-spacing: -0.055em;
}

.brand small {
  display: inline-block;
  margin-left: 5px;
  color: var(--muted);
  font-size: 13px;
  font-weight: 450;
  letter-spacing: -0.035em;
}

.time-big {
  font-size: 28px;
  font-weight: 700;
  letter-spacing: -0.055em;
  font-variant-numeric: tabular-nums;
  white-space: nowrap;
}

.time-ctl {
  display: flex;
  align-items: center;
  gap: 8px;
  margin-top: 12px;
}

.time-ctl select {
  min-height: 42px;
  padding: 7px 12px;
  border: 1px solid var(--line);
  border-radius: 10px;
  background: var(--surface);
}

.time-ctl input[type="range"] {
  flex: 1;
  min-width: 0;
  accent-color: var(--hy-blue);
  cursor: pointer;
}

.demo-tag {
  margin-top: 5px;
  color: var(--muted);
  font-size: 12px;
  letter-spacing: -0.015em;
}

/* 3. Section headings */

h2 {
  margin: 26px 0 8px;
  font-size: 18px;
  line-height: 1.4;
  font-weight: 700;
  letter-spacing: -0.045em;
}

.hint {
  margin: 0 0 14px;
  color: var(--muted);
  font-size: 13px;
  line-height: 1.65;
}

/* 4. Building filters */

.chips {
  display: flex;
  gap: 7px;
  overflow-x: auto;
  padding: 2px 0 5px;
  scrollbar-width: none;
  -webkit-overflow-scrolling: touch;
}

.chips::-webkit-scrollbar {
  display: none;
}

.chip {
  flex: none;
  min-height: 36px;
  padding: 6px 14px;

  border: 1px solid var(--line);
  border-radius: 9px;
  background: var(--surface);

  color: var(--ink);
  font-size: 13px;
  font-weight: 500;

  transition:
    background-color 0.15s ease,
    border-color 0.15s ease,
    color 0.15s ease;
}

.chip[aria-pressed="true"] {
  background: var(--hy-blue);
  border-color: var(--hy-blue);
  color: #FFFFFF;
  font-weight: 600;
}

/* 5. Recently ended / empty states */

.empty {
  padding: 20px 14px;
  border: 1px solid var(--line);
  border-radius: 12px;
  background: var(--surface);

  color: var(--muted);
  text-align: center;
  font-size: 13px;
}

/* 6. Classroom cards */

.room {
  display: grid;
  grid-template-columns: 3px minmax(0, 1fr) auto;
  align-items: center;
  gap: 0 13px;

  width: 100%;
  margin-bottom: 9px;
  padding: 13px 14px 13px 0;

  text-align: left;
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: 12px;
  overflow: hidden;

  transition:
    border-color 0.15s ease,
    background-color 0.15s ease;
}

.room:active {
  background: var(--blue-soft);
}

.room .bar {
  align-self: stretch;
  margin: -13px 0;
  background: var(--line);
}

.room.free .bar {
  background: var(--hy-blue);
}

.room.ended .bar {
  background: var(--ended);
}

.room-name {
  font-size: 15px;
  line-height: 1.45;
  font-weight: 650;
  letter-spacing: -0.04em;
}

.room-sub {
  margin-top: 3px;
  color: var(--muted);
  font-size: 12px;
}

.until {
  text-align: right;
  white-space: nowrap;
  font-variant-numeric: tabular-nums;
}

.until b {
  display: block;
  font-size: 16px;
  line-height: 1.45;
  font-weight: 700;
  letter-spacing: -0.035em;
}

.until span {
  display: block;
  margin-top: 3px;
  color: var(--muted);
  font-size: 11px;
}

.room.free .until b {
  color: var(--hy-blue);
}

.room.ended .until b {
  color: var(--ended);
}

/* 7. Timetable selectors */

.pickers {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 8px;
}

.pickers select {
  width: 100%;
  min-height: 42px;
  padding: 9px 12px;

  border: 1px solid var(--line);
  border-radius: 10px;
  background: var(--surface);
}

.days {
  display: grid;
  grid-template-columns: repeat(7, minmax(0, 1fr));
  gap: 5px;
  margin: 12px 0 16px;
}

.days button {
  min-width: 0;
  padding: 7px 0;

  border: 1px solid transparent;
  border-radius: 9px;
  background: var(--surface);

  font-size: 13px;
  font-weight: 500;
}

.days button[aria-pressed="true"] {
  background: var(--hy-blue);
  border-color: var(--hy-blue);
  color: #FFFFFF;
  font-weight: 650;
}

.grid-scroll {
  overflow-x: auto;
  -webkit-overflow-scrolling: touch;
}

.grid {
  position: relative;
  display: grid;
  grid-template-columns: 42px minmax(0, 1fr);
  min-width: 280px;
}

.hours {
  position: relative;
}

.hours div {
  position: absolute;
  right: 8px;
  transform: translateY(-50%);

  color: var(--muted);
  font-size: 11px;
  font-variant-numeric: tabular-nums;
}

.lane {
  position: relative;
  border-left: 1px solid var(--line);
  background-image:
    linear-gradient(var(--line) 1px, transparent 1px);
  background-size: 100% 52px;
}

.block {
  position: absolute;
  left: 6px;
  right: 6px;
  overflow: hidden;
  padding: 6px 8px;

  border: none;
  border-left: 3px solid var(--hy-blue);
  border-radius: 6px;

  background: var(--blue-soft);
  color: var(--ink);
  text-align: left;
}

.block b {
  display: block;
  font-size: 12px;
  font-weight: 650;
  line-height: 1.5;
}

.block span {
  color: var(--muted);
  font-size: 11px;
}

.block.is-ended {
  background: var(--ended-soft);
  border-left-color: var(--ended);
}

.nowline {
  position: absolute;
  left: -4px;
  right: 0;
  z-index: 2;
  height: 2px;
  background: var(--now);
}

.nowline::before {
  content: "";
  position: absolute;
  top: -3px;
  left: -3px;

  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--now);
}

/* 8. Status cards */

.status {
  margin-bottom: 12px;
  padding: 15px;

  border: 1px solid var(--line);
  border-radius: 12px;
  background: var(--surface);
}

.status .lbl {
  color: var(--muted);
  font-size: 12px;
}

.status .big {
  margin: 3px 0 10px;
  font-size: 18px;
  font-weight: 700;
  letter-spacing: -0.04em;
}

.tally {
  display: flex;
  gap: 18px;
  margin-bottom: 12px;
  font-variant-numeric: tabular-nums;
}

.tally div {
  color: var(--muted);
  font-size: 12px;
}

.tally b {
  margin-right: 3px;
  color: var(--ink);
  font-size: 21px;
  font-weight: 700;
}

.tally .e b {
  color: var(--ended);
}

/* 9. Buttons */

.actions {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 8px;
}

.actions .btn:last-child {
  grid-column: 1 / -1;
}

.btn {
  min-height: 42px;
  padding: 10px 13px;

  border: 1px solid var(--line);
  border-radius: 10px;
  background: var(--surface);

  font-size: 14px;
  font-weight: 550;

  transition:
    background-color 0.15s ease,
    border-color 0.15s ease;
}

.btn:active {
  background: var(--blue-soft);
}

.btn.primary {
  border-color: var(--hy-blue);
  background: var(--hy-blue);
  color: #FFFFFF;
  font-weight: 650;
}

.btn[aria-pressed="true"] {
  outline: 2px solid var(--blue);
  outline-offset: 1px;
}

.btn:disabled {
  opacity: 0.45;
  cursor: not-allowed;
}

.btn[aria-pressed="true"]:disabled {
  opacity: 1;
}

.note {
  margin-top: 8px;
  color: var(--muted);
  font-size: 12px;
}

/* 10. Authentication */

.field {
  display: flex;
  flex-direction: column;
  gap: 6px;
  margin-bottom: 12px;
}

.field input {
  width: 100%;
  min-height: 44px;
  padding: 10px 12px;

  border: 1px solid var(--line);
  border-radius: 10px;
  background: var(--surface);
}

.field input:focus {
  border-color: var(--hy-blue);
  outline: none;
  box-shadow: 0 0 0 3px var(--blue-soft);
}

.verified {
  display: flex;
  align-items: center;
  gap: 10px;

  margin-bottom: 12px;
  padding: 12px 14px;

  border: 1px solid var(--line);
  border-radius: 12px;
  background: var(--surface);
}

.verified b {
  color: var(--hy-blue);
}

.err {
  min-height: 1.2em;
  color: var(--now);
  font-size: 13px;
}

/* 11. Bottom navigation */

nav.tabs {
  position: fixed;
  left: 0;
  right: 0;
  bottom: 0;
  z-index: 10;

  background: var(--surface);
  border-top: 1px solid var(--line);
  padding-bottom: env(safe-area-inset-bottom, 0px);
}

nav.tabs .in {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  max-width: 560px;
  margin: 0 auto;
}

nav.tabs button {
  position: relative;
  min-height: 54px;
  padding: 10px 0;

  border: none;
  background: transparent;

  color: var(--muted);
  font-size: 12px;
  font-weight: 500;
}

nav.tabs button[aria-current="page"] {
  color: var(--hy-blue);
  font-weight: 700;
}

nav.tabs button[aria-current="page"]::before {
  content: "";
  position: absolute;
  top: 0;
  left: 27%;
  right: 27%;

  height: 2px;
  border-radius: 0 0 2px 2px;
  background: var(--hy-blue);
}

/* 12. Toast */

.toast {
  position: fixed;
  left: 50%;
  bottom: 78px;
  z-index: 20;
  transform: translateX(-50%);

  max-width: calc(100vw - 32px);
  padding: 10px 16px;

  border: 1px solid var(--line);
  border-radius: 10px;
  background: var(--ink);
  color: var(--surface);

  font-size: 13px;
  text-align: center;
  white-space: nowrap;

  opacity: 0;
  pointer-events: none;
  transition: opacity 0.18s ease;
}

.toast.show {
  opacity: 1;
}

/* 13. Small screens & accessibility */

@media (max-width: 380px) {
  .wrap {
    padding-right: 14px;
    padding-left: 14px;
  }

  .brand {
    font-size: 17px;
  }

  .brand small {
    font-size: 11px;
  }

  .time-big {
    font-size: 25px;
  }

  .room {
    gap: 0 10px;
    padding-right: 11px;
  }

  .room-name {
    font-size: 14px;
  }

  .until b {
    font-size: 15px;
  }
}

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