/* ==========================================================================
   Vector Rescue — IB Physics A.1 Kinematics
   Deep-space rescue theme: near-black hull, teal instrumentation, gold alerts.
   ========================================================================== */

:root {
  --bg:        #070b14;
  --bg-2:      #0d1524;
  --panel:     #111b2e;
  --panel-2:   #16233b;
  --line:      #24344f;
  --ink:       #e8eef8;
  --ink-dim:   #93a4c0;
  --ink-faint: #5f7190;
  --teal:      #2fd6c3;
  --teal-dark: #17806f;
  --gold:      #ffc24a;
  --rose:      #ff6b81;
  --violet:    #a98bff;
  --green:     #5ce08a;
  --radius:    14px;
  --shadow:    0 10px 30px rgba(0,0,0,.45);
  --mono:      ui-monospace, "SFMono-Regular", "Cascadia Code", Consolas, monospace;
  --sans:      "Segoe UI", system-ui, -apple-system, Roboto, Helvetica, Arial, sans-serif;
}

* { box-sizing: border-box; }

html, body {
  margin: 0;
  padding: 0;
  background: var(--bg);
  color: var(--ink);
  font-family: var(--sans);
  font-size: 16px;
  line-height: 1.5;
  -webkit-text-size-adjust: 100%;
}

body {
  min-height: 100vh;
  background-image:
    radial-gradient(1200px 600px at 15% -10%, rgba(47,214,195,.10), transparent 60%),
    radial-gradient(900px 500px at 95% 0%, rgba(169,139,255,.10), transparent 60%);
  background-attachment: fixed;
}

h1, h2, h3 { line-height: 1.2; margin: 0 0 .4em; font-weight: 700; letter-spacing: .01em; }
h1 { font-size: clamp(1.8rem, 5vw, 3rem); }
h2 { font-size: clamp(1.25rem, 3vw, 1.75rem); }
h3 { font-size: 1.05rem; }
p  { margin: 0 0 .8em; }
a  { color: var(--teal); }

.screen {
  max-width: 1080px;
  margin: 0 auto;
  padding: 18px 16px 72px;
}

/* ------------------------------ HUD ------------------------------------ */

.hud {
  position: sticky;
  top: 0;
  z-index: 40;
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 8px 14px;
  background: rgba(9, 14, 24, .92);
  border-bottom: 1px solid var(--line);
  backdrop-filter: blur(8px);
}

.hud__home {
  background: var(--panel-2);
  color: var(--ink);
  border: 1px solid var(--line);
  border-radius: 9px;
  padding: 7px 12px;
  font: inherit;
  font-size: .85rem;
  cursor: pointer;
}
.hud__home:hover { border-color: var(--teal); color: var(--teal); }

.hud__id { display: flex; flex-direction: column; line-height: 1.15; min-width: 0; }
.hud__rank { font-size: .68rem; letter-spacing: .14em; text-transform: uppercase; color: var(--gold); }
.hud__name { font-size: .9rem; font-weight: 600; white-space: nowrap; overflow: hidden; text-overflow: ellipsis; }

.hud__xpwrap { flex: 1; display: flex; align-items: center; gap: 8px; min-width: 60px; }
.hud__xpbar { flex: 1; height: 8px; background: var(--panel-2); border-radius: 99px; overflow: hidden; border: 1px solid var(--line); }
.hud__xpfill { height: 100%; width: 0%; background: linear-gradient(90deg, var(--teal-dark), var(--teal)); transition: width .45s ease; }
.hud__xptext { font: 600 .78rem var(--mono); color: var(--ink-dim); white-space: nowrap; }

.hud__lives { font-size: 1rem; letter-spacing: .08em; color: var(--gold); white-space: nowrap; }

/* ------------------------------ Cards ---------------------------------- */

.panel {
  background: linear-gradient(180deg, var(--panel), var(--bg-2));
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 18px;
  box-shadow: var(--shadow);
  margin-bottom: 16px;
}

.panel--flush { padding: 0; overflow: hidden; }

.eyebrow {
  font-size: .7rem;
  letter-spacing: .18em;
  text-transform: uppercase;
  color: var(--teal);
  font-weight: 700;
  margin-bottom: 6px;
}

.muted { color: var(--ink-dim); }
.small { font-size: .85rem; }
.mono  { font-family: var(--mono); }
.center{ text-align: center; }

/* ------------------------------ Buttons -------------------------------- */

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  background: var(--panel-2);
  color: var(--ink);
  border: 1px solid var(--line);
  border-radius: 10px;
  padding: 11px 18px;
  font: 600 .95rem var(--sans);
  cursor: pointer;
  transition: transform .08s ease, border-color .15s ease, background .15s ease;
}
.btn:hover:not(:disabled) { border-color: var(--teal); background: #1b2c47; }
.btn:active:not(:disabled) { transform: translateY(1px); }
.btn:disabled { opacity: .45; cursor: not-allowed; }

.btn--primary {
  background: linear-gradient(180deg, var(--teal), var(--teal-dark));
  color: #04231f;
  border-color: transparent;
  font-weight: 700;
}
.btn--primary:hover:not(:disabled) { background: linear-gradient(180deg, #4ce6d4, #1a9384); }

.btn--gold { background: linear-gradient(180deg, var(--gold), #d9932a); color: #241703; border-color: transparent; font-weight: 700; }
.btn--ghost { background: transparent; }
.btn--sm { padding: 7px 12px; font-size: .82rem; }
.btn--wide { width: 100%; }

.btn-row { display: flex; flex-wrap: wrap; gap: 10px; }

/* ------------------------------ Title screen --------------------------- */

.title { text-align: center; padding: 6vh 0 2vh; }
.title__logo {
  font-size: clamp(2.2rem, 8vw, 4.2rem);
  font-weight: 800;
  letter-spacing: .04em;
  background: linear-gradient(92deg, var(--teal), var(--violet) 55%, var(--gold));
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
  margin-bottom: 4px;
}
.title__sub { color: var(--ink-dim); font-size: 1.02rem; margin-bottom: 26px; }

.title__card { max-width: 560px; margin: 0 auto; text-align: left; }

.field { display: block; margin-bottom: 14px; }
.field > span { display: block; font-size: .78rem; letter-spacing: .1em; text-transform: uppercase; color: var(--ink-dim); margin-bottom: 6px; }
.field input, .field select {
  width: 100%;
  background: var(--bg);
  color: var(--ink);
  border: 1px solid var(--line);
  border-radius: 10px;
  padding: 11px 13px;
  font: 500 1rem var(--sans);
}
.field input:focus, .field select:focus { outline: 2px solid var(--teal); outline-offset: 1px; }

/* ------------------------------ Mission map ---------------------------- */

.map-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 14px;
}

.zone-card {
  position: relative;
  display: flex;
  flex-direction: column;
  text-align: left;
  background: linear-gradient(160deg, var(--panel), var(--bg-2));
  border: 1px solid var(--line);
  border-left: 4px solid var(--accent, var(--teal));
  border-radius: var(--radius);
  padding: 16px;
  cursor: pointer;
  font: inherit;
  color: inherit;
  transition: transform .12s ease, border-color .15s ease, box-shadow .15s ease;
}
.zone-card:hover:not(:disabled) { transform: translateY(-3px); box-shadow: var(--shadow); border-color: var(--accent, var(--teal)); }
.zone-card:disabled { opacity: .5; cursor: not-allowed; }

.zone-card__tag { font: 700 .68rem var(--mono); letter-spacing: .16em; color: var(--accent, var(--teal)); text-transform: uppercase; }
.zone-card__name { font-size: 1.22rem; font-weight: 700; margin: 4px 0 2px; }
.zone-card__sub { font-size: .86rem; color: var(--ink-dim); margin-bottom: 10px; }
.zone-card__skills { font-size: .78rem; color: var(--ink-dim); margin-bottom: 12px; }
.zone-card__foot { margin-top: auto; display: flex; align-items: center; justify-content: space-between; gap: 8px; }
.zone-card__stars { color: var(--gold); letter-spacing: .1em; font-size: 1rem; }
.zone-card__best { font: 600 .76rem var(--mono); color: var(--ink-dim); }
.zone-card__lock { position: absolute; top: 14px; right: 14px; font-size: 1.1rem; }

/* ------------------------------ Game stage ----------------------------- */

.stage {
  display: grid;
  grid-template-columns: minmax(0, 1.35fr) minmax(0, 1fr);
  gap: 16px;
  align-items: start;
}
@media (max-width: 820px) { .stage { grid-template-columns: 1fr; } }

.canvas-wrap {
  position: relative;
  background: #050a12;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  overflow: hidden;
}
canvas { display: block; width: 100%; height: auto; touch-action: manipulation; }

.readout {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(118px, 1fr));
  gap: 8px;
  margin-top: 12px;
}
.readout__cell {
  background: var(--bg);
  border: 1px solid var(--line);
  border-radius: 9px;
  padding: 8px 10px;
}
.readout__k { display: block; font-size: .65rem; letter-spacing: .12em; text-transform: uppercase; color: var(--ink-dim); }
.readout__v { display: block; font: 700 .95rem var(--mono); color: var(--teal); white-space: nowrap; }

/* ------------------------------ Questions ------------------------------ */

.q__stem { font-size: 1.04rem; margin-bottom: 12px; }
.q__stem code { background: var(--bg); padding: 1px 5px; border-radius: 5px; font-family: var(--mono); }

.opts { display: grid; gap: 9px; }
.opt {
  display: flex;
  align-items: flex-start;
  gap: 10px;
  text-align: left;
  background: var(--bg);
  color: var(--ink);
  border: 1px solid var(--line);
  border-radius: 10px;
  padding: 11px 13px;
  font: 500 .95rem var(--sans);
  cursor: pointer;
  transition: border-color .12s ease, background .12s ease;
}
.opt:hover:not(:disabled) { border-color: var(--teal); }
.opt:disabled { cursor: default; }
.opt__key {
  flex: none;
  width: 24px; height: 24px;
  display: grid; place-items: center;
  border-radius: 6px;
  background: var(--panel-2);
  font: 700 .8rem var(--mono);
  color: var(--ink-dim);
}
.opt--right { border-color: var(--green); background: rgba(92,224,138,.10); }
.opt--right .opt__key { background: var(--green); color: #04240f; }
.opt--wrong { border-color: var(--rose); background: rgba(255,107,129,.10); }
.opt--wrong .opt__key { background: var(--rose); color: #2b0509; }

.feedback {
  margin-top: 12px;
  border-radius: 10px;
  padding: 12px 14px;
  border: 1px solid var(--line);
  background: var(--bg);
  font-size: .92rem;
}
.feedback--right { border-color: var(--green); }
.feedback--wrong { border-color: var(--gold); }
.feedback__title { font-weight: 700; margin-bottom: 4px; }
.feedback--right .feedback__title { color: var(--green); }
.feedback--wrong .feedback__title { color: var(--gold); }
.feedback__work { font-family: var(--mono); font-size: .85rem; color: var(--ink-dim); white-space: pre-wrap; margin-top: 6px; }

.numin {
  display: flex; gap: 8px; align-items: center; flex-wrap: wrap;
}
.numin input {
  flex: 1 1 130px;
  background: var(--bg); color: var(--ink);
  border: 1px solid var(--line); border-radius: 10px;
  padding: 11px 13px; font: 600 1rem var(--mono);
}
.numin input:focus { outline: 2px solid var(--teal); outline-offset: 1px; }
.numin__unit { font: 600 .95rem var(--mono); color: var(--ink-dim); }

/* ------------------------------ Sliders -------------------------------- */

.ctrl { margin-bottom: 14px; }
.ctrl__head { display: flex; justify-content: space-between; align-items: baseline; margin-bottom: 4px; }
.ctrl__label { font-size: .8rem; letter-spacing: .08em; text-transform: uppercase; color: var(--ink-dim); }
.ctrl__val { font: 700 .95rem var(--mono); color: var(--gold); }

input[type="range"] {
  -webkit-appearance: none; appearance: none;
  width: 100%; height: 26px; background: transparent; cursor: pointer; margin: 0;
}
input[type="range"]::-webkit-slider-runnable-track { height: 6px; background: var(--panel-2); border-radius: 99px; border: 1px solid var(--line); }
input[type="range"]::-moz-range-track { height: 6px; background: var(--panel-2); border-radius: 99px; border: 1px solid var(--line); }
input[type="range"]::-webkit-slider-thumb {
  -webkit-appearance: none; appearance: none;
  width: 20px; height: 20px; border-radius: 50%;
  background: var(--teal); border: 2px solid #04231f; margin-top: -8px;
}
input[type="range"]::-moz-range-thumb { width: 20px; height: 20px; border-radius: 50%; background: var(--teal); border: 2px solid #04231f; }

/* ------------------------------ Misc ----------------------------------- */

.chips { display: flex; flex-wrap: wrap; gap: 7px; margin-bottom: 12px; }
.chip {
  font: 600 .74rem var(--mono);
  background: var(--panel-2);
  border: 1px solid var(--line);
  color: var(--ink-dim);
  border-radius: 99px;
  padding: 4px 10px;
}
.chip--on { border-color: var(--teal); color: var(--teal); }
.chip--gold { border-color: var(--gold); color: var(--gold); }

.progress-dots { display: flex; gap: 6px; }
.dot { width: 10px; height: 10px; border-radius: 50%; background: var(--panel-2); border: 1px solid var(--line); }
.dot--done { background: var(--teal); border-color: var(--teal); }
.dot--miss { background: var(--rose); border-color: var(--rose); }
.dot--now  { box-shadow: 0 0 0 3px rgba(47,214,195,.25); }

table.data { width: 100%; border-collapse: collapse; font-size: .9rem; }
table.data th, table.data td { text-align: left; padding: 7px 9px; border-bottom: 1px solid var(--line); }
table.data th { font-size: .72rem; letter-spacing: .1em; text-transform: uppercase; color: var(--ink-dim); font-weight: 700; }
table.data td.num { font-family: var(--mono); }

ul.tight { margin: 0 0 .8em; padding-left: 1.1em; }
ul.tight li { margin-bottom: .3em; }

/* ------------------------------ Toast ---------------------------------- */

.toast {
  position: fixed;
  left: 50%;
  bottom: 24px;
  transform: translate(-50%, 18px);
  background: var(--panel-2);
  border: 1px solid var(--teal);
  color: var(--ink);
  padding: 10px 18px;
  border-radius: 99px;
  font-weight: 600;
  font-size: .92rem;
  box-shadow: var(--shadow);
  opacity: 0;
  pointer-events: none;
  transition: opacity .25s ease, transform .25s ease;
  z-index: 60;
  max-width: 90vw;
  text-align: center;
}
.toast--on { opacity: 1; transform: translate(-50%, 0); }

/* ------------------------------ Modal ---------------------------------- */

.modal {
  position: fixed; inset: 0; z-index: 70;
  background: rgba(4, 7, 13, .78);
  display: grid; place-items: center;
  padding: 18px;
  backdrop-filter: blur(4px);
}
.modal[hidden] { display: none; }
.modal__box {
  width: min(560px, 100%);
  max-height: 88vh;
  overflow-y: auto;
  background: linear-gradient(180deg, var(--panel), var(--bg-2));
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 22px;
  box-shadow: var(--shadow);
}
.modal__actions { display: flex; flex-wrap: wrap; gap: 10px; margin-top: 18px; }

.stars-big { font-size: 2rem; color: var(--gold); letter-spacing: .12em; text-align: center; margin: 6px 0 14px; }

/* ------------------------------ Badges --------------------------------- */

.badge-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(150px, 1fr)); gap: 10px; }
.badge {
  background: var(--bg); border: 1px solid var(--line); border-radius: 10px;
  padding: 10px 12px; font-size: .82rem;
}
.badge--on { border-color: var(--gold); }
.badge__icon { font-size: 1.3rem; display: block; margin-bottom: 2px; filter: grayscale(1) opacity(.45); }
.badge--on .badge__icon { filter: none; }
.badge__name { display: block; font-weight: 700; line-height: 1.25; }
.badge__desc { display: block; color: var(--ink-dim); font-size: .75rem; margin-top: 2px; }

/* ------------------------------ Helpers -------------------------------- */

.row { display: flex; gap: 12px; align-items: center; flex-wrap: wrap; }
.spread { display: flex; justify-content: space-between; align-items: center; gap: 12px; flex-wrap: wrap; }
.mt { margin-top: 14px; }
.mb0 { margin-bottom: 0; }
.nowrap { white-space: nowrap; }

@media (prefers-reduced-motion: reduce) {
  * { animation-duration: .001ms !important; transition-duration: .001ms !important; }
}