/* =========================================================
   Block Unclog: Color Escape — Light polyomino playground
   Differentiated layout: interlocking stud board + exit dock
   ========================================================= */

:root {
  --bg: #eef3ff;
  --bg-elevated: #ffffff;
  --ink: #1a2744;
  --ink-muted: #4a5d7a;
  --line: rgba(26, 39, 68, 0.1);

  --red: #e53935;
  --red-deep: #c62828;
  --blue: #2979ff;
  --blue-deep: #1565c0;
  --green: #43a047;
  --green-deep: #2e7d32;
  --yellow: #f9a825;
  --yellow-deep: #f57f17;
  --cyan: #00bcd4;
  --white-block: #f5f7fb;

  --cta: #ff6f00;
  --cta-ink: #fff8f0;
  --glow-soft: rgba(41, 121, 255, 0.18);

  --radius-block: 28px;
  --radius-pill: 999px;
  --shadow-block: 0 10px 0 rgba(26, 39, 68, 0.12), 0 18px 36px rgba(26, 39, 68, 0.1);
  --shadow-press: 0 4px 0 rgba(26, 39, 68, 0.14), 0 8px 18px rgba(26, 39, 68, 0.1);

  --font-display: "Comfortaa", system-ui, sans-serif;
  --font-body: "Karla", system-ui, sans-serif;

  --nav-h: 72px;
  --ease: cubic-bezier(0.22, 1, 0.36, 1);
}

[data-theme="dark"] {
  --bg: #12182a;
  --bg-elevated: #1c2440;
  --ink: #eef2ff;
  --ink-muted: #a8b4d0;
  --line: rgba(238, 242, 255, 0.12);
  --white-block: #2a3354;
  --glow-soft: rgba(0, 188, 212, 0.2);
  --shadow-block: 0 10px 0 rgba(0, 0, 0, 0.35), 0 18px 36px rgba(0, 0, 0, 0.35);
  --shadow-press: 0 4px 0 rgba(0, 0, 0, 0.4), 0 8px 18px rgba(0, 0, 0, 0.3);
}

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

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  font-family: var(--font-body);
  font-size: 1.05rem;
  line-height: 1.6;
  color: var(--ink);
  background: var(--bg);
  overflow-x: hidden;
}

img {
  max-width: 100%;
  height: auto;
  display: block;
}

a {
  color: inherit;
  text-decoration: none;
}

button {
  font: inherit;
  cursor: pointer;
  border: none;
  background: none;
}

.skip-link {
  position: absolute;
  left: -999px;
  top: 0;
  background: var(--ink);
  color: #fff;
  padding: 0.75rem 1rem;
  z-index: 9999;
}

.skip-link:focus {
  left: 1rem;
  top: 1rem;
}

/* ---------- Playground ambience ---------- */
.playground {
  position: fixed;
  inset: 0;
  z-index: -1;
  pointer-events: none;
}

.playground__wash {
  position: absolute;
  inset: 0;
  background:
    radial-gradient(ellipse 80% 50% at 15% 10%, rgba(41, 121, 255, 0.16), transparent 55%),
    radial-gradient(ellipse 70% 45% at 90% 20%, rgba(249, 168, 37, 0.14), transparent 50%),
    radial-gradient(ellipse 60% 40% at 50% 90%, rgba(67, 160, 71, 0.12), transparent 55%),
    var(--bg);
}

.playground__dots {
  position: absolute;
  inset: 0;
  opacity: 0.35;
  background-image: radial-gradient(circle, rgba(26, 39, 68, 0.12) 1px, transparent 1px);
  background-size: 22px 22px;
}

[data-theme="dark"] .playground__dots {
  opacity: 0.2;
  background-image: radial-gradient(circle, rgba(238, 242, 255, 0.15) 1px, transparent 1px);
}

/* ---------- Nav ---------- */
.stud-nav {
  position: sticky;
  top: 0;
  z-index: 100;
  padding: 0.75rem 1.25rem;
  transition: background 0.25s var(--ease), box-shadow 0.25s var(--ease);
}

.stud-nav.is-scrolled {
  background: color-mix(in srgb, var(--bg-elevated) 88%, transparent);
  backdrop-filter: blur(12px);
  box-shadow: 0 8px 24px rgba(26, 39, 68, 0.08);
}

.stud-nav__inner {
  max-width: 1120px;
  margin: 0 auto;
  display: flex;
  align-items: center;
  gap: 1rem;
  min-height: calc(var(--nav-h) - 1.5rem);
  padding: 0.35rem 0.6rem 0.35rem 0.75rem;
  background: var(--bg-elevated);
  border-radius: var(--radius-pill);
  box-shadow: var(--shadow-press);
  border: 2px solid var(--line);
}

.stud-nav__brand {
  display: flex;
  align-items: center;
  gap: 0.55rem;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 1rem;
  flex-shrink: 0;
}

.stud-nav__logo {
  border-radius: 12px;
  box-shadow: 0 3px 0 rgba(26, 39, 68, 0.15);
}

.stud-nav__links {
  display: flex;
  align-items: center;
  gap: 0.15rem;
  margin-left: auto;
}

.stud-nav__links a {
  padding: 0.45rem 0.85rem;
  border-radius: var(--radius-pill);
  font-weight: 600;
  font-size: 0.92rem;
  color: var(--ink-muted);
  transition: color 0.2s, background 0.2s;
}

.stud-nav__links a:hover,
.stud-nav__links a:focus-visible {
  color: var(--ink);
  background: color-mix(in srgb, var(--blue) 12%, transparent);
  outline: none;
}

.stud-nav__actions {
  display: flex;
  align-items: center;
  gap: 0.45rem;
  margin-left: 0.35rem;
}

.theme-toggle {
  width: 42px;
  height: 42px;
  border-radius: 14px;
  display: grid;
  place-items: center;
  background: color-mix(in srgb, var(--blue) 10%, var(--bg));
  color: var(--ink);
  transition: background 0.2s, transform 0.15s;
}

.theme-toggle:hover {
  background: color-mix(in srgb, var(--blue) 18%, var(--bg));
}

.theme-toggle:active {
  transform: translateY(1px);
}

.theme-toggle .icon-sun {
  display: none;
}

[data-theme="dark"] .theme-toggle .icon-moon {
  display: none;
}

[data-theme="dark"] .theme-toggle .icon-sun {
  display: block;
}

.stud-nav__burger {
  display: none;
  width: 42px;
  height: 42px;
  border-radius: 14px;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 5px;
  background: color-mix(in srgb, var(--blue) 10%, var(--bg));
}

.stud-nav__burger span {
  display: block;
  width: 18px;
  height: 2.5px;
  border-radius: 2px;
  background: var(--ink);
  transition: transform 0.2s, opacity 0.2s;
}

.stud-nav__burger[aria-expanded="true"] span:nth-child(1) {
  transform: translateY(7.5px) rotate(45deg);
}

.stud-nav__burger[aria-expanded="true"] span:nth-child(2) {
  opacity: 0;
}

.stud-nav__burger[aria-expanded="true"] span:nth-child(3) {
  transform: translateY(-7.5px) rotate(-45deg);
}

/* ---------- Exit dock (novel side nav) ---------- */
.exit-dock {
  position: fixed;
  right: 1.1rem;
  top: 50%;
  transform: translateY(-50%);
  z-index: 90;
  display: flex;
  flex-direction: column;
  gap: 0.65rem;
}

.exit-dock__slot {
  width: 18px;
  height: 42px;
  border-radius: 10px 4px 4px 10px;
  box-shadow: inset 0 -3px 0 rgba(0, 0, 0, 0.2), 0 4px 10px rgba(26, 39, 68, 0.15);
  display: grid;
  place-items: center;
  transition: transform 0.2s var(--ease), box-shadow 0.2s;
}

.exit-dock__slot span {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: rgba(255, 255, 255, 0.85);
  box-shadow: inset 0 1px 2px rgba(255, 255, 255, 0.9);
  opacity: 0.55;
  transition: opacity 0.2s, transform 0.2s;
}

.exit-dock__slot.is-active {
  transform: translateX(-4px) scale(1.08);
}

.exit-dock__slot.is-active span {
  opacity: 1;
  transform: scale(1.15);
}

.exit-dock__slot--red { background: linear-gradient(180deg, #ef5350, var(--red-deep)); }
.exit-dock__slot--blue { background: linear-gradient(180deg, #5c9dff, var(--blue-deep)); }
.exit-dock__slot--green { background: linear-gradient(180deg, #66bb6a, var(--green-deep)); }
.exit-dock__slot--yellow { background: linear-gradient(180deg, #ffca28, var(--yellow-deep)); }
.exit-dock__slot--cyan { background: linear-gradient(180deg, #26c6da, #00838f); }

/* ---------- Buttons ---------- */
.btn-exit,
.btn-stud {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  padding: 0.85rem 1.35rem;
  border-radius: 18px;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 0.95rem;
  transition: transform 0.15s var(--ease), box-shadow 0.15s, filter 0.15s;
}

.btn-exit {
  color: var(--cta-ink);
  background: linear-gradient(180deg, #ff9800, var(--cta));
  box-shadow: 0 6px 0 #c05600, 0 12px 24px rgba(255, 111, 0, 0.28);
}

.btn-exit:hover {
  filter: brightness(1.05);
}

.btn-exit:active {
  transform: translateY(3px);
  box-shadow: 0 3px 0 #c05600, 0 6px 12px rgba(255, 111, 0, 0.22);
}

.btn-exit--sm {
  padding: 0.55rem 1rem;
  font-size: 0.85rem;
  border-radius: 14px;
  box-shadow: 0 4px 0 #c05600, 0 8px 16px rgba(255, 111, 0, 0.22);
}

.btn-exit--lg {
  padding: 1rem 1.6rem;
  font-size: 1.05rem;
}

.btn-stud {
  color: var(--ink);
  background: var(--bg-elevated);
  border: 2px solid var(--line);
  box-shadow: 0 5px 0 rgba(26, 39, 68, 0.1);
}

.btn-stud:hover {
  background: color-mix(in srgb, var(--blue) 8%, var(--bg-elevated));
}

.btn-stud:active {
  transform: translateY(2px);
  box-shadow: 0 2px 0 rgba(26, 39, 68, 0.1);
}

.btn-stud--lg {
  padding: 1rem 1.6rem;
  font-size: 1.05rem;
}

/* ---------- Sections shared ---------- */
.section-head {
  text-align: center;
  max-width: 640px;
  margin: 0 auto 2.5rem;
  padding: 0 1.25rem;
}

.section-head h2 {
  font-family: var(--font-display);
  font-size: clamp(1.7rem, 3.5vw, 2.4rem);
  font-weight: 700;
  letter-spacing: -0.02em;
  margin: 0.65rem 0 0.75rem;
  line-height: 1.2;
}

.section-head__lead {
  margin: 0;
  color: var(--ink-muted);
}

.chip {
  display: inline-flex;
  align-items: center;
  padding: 0.35rem 0.9rem;
  border-radius: var(--radius-pill);
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 0.78rem;
  letter-spacing: 0.04em;
  text-transform: uppercase;
  color: #fff;
}

.chip--blue { background: var(--blue); }
.chip--green { background: var(--green); }
.chip--yellow { background: var(--yellow); color: #3a2a00; }
.chip--cyan { background: var(--cyan); }

/* ---------- Hero ---------- */
.hero {
  max-width: 1180px;
  margin: 0 auto;
  padding: 1.5rem 1.25rem 4rem;
  display: grid;
  grid-template-columns: 1.15fr 0.85fr;
  gap: 2.5rem;
  align-items: center;
}

.hero__board {
  position: relative;
  min-height: 420px;
  display: grid;
  place-items: center;
}

.polyomino-board {
  position: absolute;
  width: min(100%, 420px);
  aspect-ratio: 1;
  display: grid;
  grid-template-columns: 1fr 1fr;
  grid-template-rows: 1fr 1fr;
  gap: 10px;
  padding: 14px;
  border-radius: 40px;
  background: color-mix(in srgb, var(--bg-elevated) 70%, transparent);
  box-shadow: var(--shadow-block);
  border: 3px solid var(--line);
  animation: board-breathe 6s ease-in-out infinite;
}

.poly {
  border-radius: 22px;
  display: grid;
  place-items: center;
  gap: 6px;
  box-shadow:
    inset 0 3px 0 rgba(255, 255, 255, 0.35),
    inset 0 -6px 0 rgba(0, 0, 0, 0.15),
    0 8px 0 rgba(0, 0, 0, 0.12);
  position: relative;
}

.poly .stud {
  width: 22%;
  aspect-ratio: 1;
  border-radius: 50%;
  background: rgba(255, 255, 255, 0.28);
  box-shadow:
    inset 0 2px 3px rgba(255, 255, 255, 0.55),
    inset 0 -2px 3px rgba(0, 0, 0, 0.18),
    0 2px 0 rgba(0, 0, 0, 0.12);
}

.poly--blue {
  grid-column: 1;
  grid-row: 1;
  background: linear-gradient(160deg, #5c9dff, var(--blue));
  clip-path: polygon(0 0, 100% 0, 100% 48%, 52% 48%, 52% 100%, 0 100%);
  animation: slide-nudge 5s ease-in-out infinite;
}

.poly--green {
  grid-column: 2;
  grid-row: 1;
  background: linear-gradient(160deg, #66bb6a, var(--green));
  clip-path: polygon(0 0, 100% 0, 100% 100%, 48% 100%, 48% 48%, 0 48%);
  animation: slide-nudge 5.5s ease-in-out infinite reverse;
}

.poly--red {
  position: absolute;
  left: 50%;
  top: 50%;
  width: 38%;
  aspect-ratio: 1;
  transform: translate(-50%, -50%);
  z-index: 2;
  background: linear-gradient(160deg, #ef5350, var(--red));
  display: grid;
  grid-template-columns: 1fr 1fr;
  grid-template-rows: 1fr 1fr;
  place-items: center;
  padding: 12%;
  animation: center-pulse 4s ease-in-out infinite;
}

.poly--red .stud {
  width: 55%;
}

.poly--yellow {
  grid-column: 1;
  grid-row: 2;
  background: linear-gradient(160deg, #ffca28, var(--yellow));
  clip-path: polygon(0 0, 52% 0, 52% 52%, 100% 52%, 100% 100%, 0 100%);
  animation: slide-nudge 6s ease-in-out infinite;
}

.poly--white {
  grid-column: 2;
  grid-row: 2;
  background: linear-gradient(160deg, #ffffff, #e8ecf5);
  clip-path: polygon(48% 0, 100% 0, 100% 100%, 0 100%, 0 52%, 48% 52%);
  animation: slide-nudge 5.2s ease-in-out infinite reverse;
}

[data-theme="dark"] .poly--white {
  background: linear-gradient(160deg, #dfe6f5, #b8c2d9);
}

.hero__copy {
  position: relative;
  z-index: 3;
  text-align: center;
  padding: 1.25rem 1rem;
  max-width: 440px;
  margin: 0 auto;
}

.hero__brand {
  display: inline-flex;
  align-items: center;
  gap: 0.6rem;
  margin: 0 0 0.75rem;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 1.05rem;
}

.hero__brand img {
  border-radius: 14px;
  box-shadow: 0 4px 0 rgba(26, 39, 68, 0.15);
}

.brand-3d {
  background: linear-gradient(180deg, #5c9dff, var(--blue));
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
  filter: drop-shadow(0 2px 0 rgba(21, 101, 192, 0.35));
}

.hero h1 {
  font-family: var(--font-display);
  font-size: clamp(2.1rem, 4.5vw, 3.1rem);
  font-weight: 700;
  line-height: 1.15;
  margin: 0 0 1rem;
  letter-spacing: -0.02em;
}

.hero h1 .word {
  display: inline-block;
  margin-right: 0.2em;
}

.word--yellow {
  color: var(--yellow-deep);
  text-shadow: 0 2px 0 rgba(245, 127, 23, 0.25);
}

.word--cyan {
  color: #00838f;
  text-shadow: 0 2px 0 rgba(0, 131, 143, 0.25);
}

.word--green {
  color: var(--green-deep);
  text-shadow: 0 2px 0 rgba(46, 125, 50, 0.25);
}

[data-theme="dark"] .word--yellow { color: #ffca28; }
[data-theme="dark"] .word--cyan { color: #4dd0e1; }
[data-theme="dark"] .word--green { color: #81c784; }

.hero__lead {
  margin: 0 0 1.4rem;
  color: var(--ink-muted);
  font-size: 1.02rem;
}

.hero__cta {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem;
  justify-content: center;
}

.hero__phone {
  position: relative;
  display: grid;
  place-items: center;
}

.phone-shell {
  width: min(100%, 300px);
  border-radius: 36px;
  padding: 12px;
  background: linear-gradient(160deg, #3d4f7c, #1e2a4a);
  box-shadow:
    0 0 0 3px rgba(41, 121, 255, 0.25),
    0 24px 48px rgba(26, 39, 68, 0.22),
    0 0 60px var(--glow-soft);
}

.phone-shell__bezel {
  border-radius: 28px;
  overflow: hidden;
  background: #0d1224;
  aspect-ratio: 9 / 16;
}

.phone-shell__shot {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.float-exits {
  position: absolute;
  inset: 0;
  pointer-events: none;
}

.float-exit {
  position: absolute;
  width: 28px;
  height: 48px;
  border-radius: 10px;
  box-shadow: inset 0 -3px 0 rgba(0, 0, 0, 0.2);
  animation: float-y 4s ease-in-out infinite;
}

.float-exit--red {
  background: var(--red);
  top: 12%;
  left: 4%;
}

.float-exit--blue {
  background: var(--blue);
  top: 40%;
  right: 2%;
  animation-delay: -1.2s;
}

.float-exit--green {
  background: var(--green);
  bottom: 14%;
  left: 8%;
  animation-delay: -2.4s;
}

@keyframes board-breathe {
  0%, 100% { transform: scale(1); }
  50% { transform: scale(1.015); }
}

@keyframes slide-nudge {
  0%, 100% { transform: translate(0, 0); }
  50% { transform: translate(3px, -2px); }
}

@keyframes center-pulse {
  0%, 100% { transform: translate(-50%, -50%) scale(1); }
  50% { transform: translate(-50%, -50%) scale(1.04); }
}

@keyframes float-y {
  0%, 100% { transform: translateY(0); }
  50% { transform: translateY(-10px); }
}

/* ---------- Features bento ---------- */
.features {
  padding: 4rem 1.25rem 5rem;
  max-width: 1100px;
  margin: 0 auto;
}

.poly-bento {
  display: grid;
  grid-template-columns: 1.1fr 1fr 1fr;
  grid-template-rows: auto auto;
  gap: 1rem;
}

.bento-block {
  position: relative;
  padding: 1.6rem 1.4rem 1.5rem;
  border-radius: var(--radius-block);
  color: #fff;
  box-shadow: var(--shadow-block);
  overflow: hidden;
  transition: transform 0.2s var(--ease);
}

.bento-block:hover {
  transform: translateY(-4px);
}

.bento-block__studs {
  display: flex;
  gap: 0.45rem;
  margin-bottom: 1rem;
}

.bento-block__studs span {
  width: 18px;
  height: 18px;
  border-radius: 50%;
  background: rgba(255, 255, 255, 0.28);
  box-shadow:
    inset 0 2px 2px rgba(255, 255, 255, 0.5),
    inset 0 -2px 2px rgba(0, 0, 0, 0.15);
}

.bento-block i {
  width: 28px;
  height: 28px;
  margin-bottom: 0.65rem;
}

.bento-block h3 {
  font-family: var(--font-display);
  font-size: 1.25rem;
  margin: 0 0 0.5rem;
}

.bento-block p {
  margin: 0;
  opacity: 0.92;
  font-size: 0.98rem;
}

.bento-block--tall {
  grid-row: span 2;
  display: flex;
  flex-direction: column;
  justify-content: flex-end;
  min-height: 320px;
}

.bento-block--wide {
  grid-column: span 2;
}

.bento-block--red { background: linear-gradient(155deg, #ef5350, var(--red-deep)); }
.bento-block--blue { background: linear-gradient(155deg, #5c9dff, var(--blue-deep)); }
.bento-block--green { background: linear-gradient(155deg, #66bb6a, var(--green-deep)); }
.bento-block--yellow {
  background: linear-gradient(155deg, #ffca28, var(--yellow-deep));
  color: #2a2200;
}

.bento-block--yellow .bento-block__studs span {
  background: rgba(255, 255, 255, 0.45);
}

/* ---------- How to ---------- */
.howto {
  padding: 3rem 1.25rem 5rem;
  max-width: 1000px;
  margin: 0 auto;
}

.escape-channel {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 0;
  position: relative;
}

.escape-step {
  display: flex;
  flex-direction: column;
  align-items: center;
  text-align: center;
  position: relative;
  padding: 0 0.75rem;
}

.escape-step__gate {
  width: 56px;
  height: 56px;
  border-radius: 18px;
  display: grid;
  place-items: center;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 1.35rem;
  color: #fff;
  margin-bottom: 1rem;
  box-shadow: inset 0 -4px 0 rgba(0, 0, 0, 0.2), 0 8px 16px rgba(26, 39, 68, 0.12);
  z-index: 1;
}

.escape-step__gate--red { background: linear-gradient(180deg, #ef5350, var(--red-deep)); }
.escape-step__gate--blue { background: linear-gradient(180deg, #5c9dff, var(--blue-deep)); }
.escape-step__gate--green { background: linear-gradient(180deg, #66bb6a, var(--green-deep)); }

.escape-step__card {
  background: var(--bg-elevated);
  border-radius: 24px;
  padding: 1.35rem 1.1rem;
  border: 2px solid var(--line);
  box-shadow: var(--shadow-press);
  width: 100%;
}

.escape-step__card h3 {
  font-family: var(--font-display);
  margin: 0 0 0.5rem;
  font-size: 1.1rem;
}

.escape-step__card p {
  margin: 0;
  color: var(--ink-muted);
  font-size: 0.95rem;
}

.escape-step__arrow {
  position: absolute;
  top: 26px;
  right: -12%;
  width: 24%;
  height: 4px;
  border-radius: 4px;
  background: linear-gradient(90deg, color-mix(in srgb, var(--blue) 50%, transparent), color-mix(in srgb, var(--green) 50%, transparent));
}

.escape-step:last-child .escape-step__arrow {
  display: none;
}

/* ---------- Gallery ---------- */
.gallery {
  padding: 3rem 1.25rem 5rem;
  max-width: 1100px;
  margin: 0 auto;
}

.gallery__tiles {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1.25rem;
  align-items: end;
}

.screen-tile {
  margin: 0;
  background: var(--bg-elevated);
  border-radius: 28px;
  padding: 0.75rem 0.75rem 1rem;
  border: 2px solid var(--line);
  box-shadow: var(--shadow-block);
  transition: transform 0.25s var(--ease);
}

.screen-tile:hover {
  transform: translateY(-6px) rotate(0deg) !important;
}

.screen-tile img {
  width: 100%;
  aspect-ratio: 9 / 16;
  object-fit: cover;
  border-radius: 20px;
  background: #1a1040;
}

.screen-tile figcaption {
  font-family: var(--font-display);
  font-weight: 700;
  text-align: center;
  margin-top: 0.75rem;
  font-size: 0.95rem;
}

.screen-tile--a { transform: rotate(-3deg); }
.screen-tile--b { transform: translateY(-18px); }
.screen-tile--c { transform: rotate(3deg); }

/* ---------- Download ---------- */
.download {
  padding: 2rem 1.25rem 5rem;
  max-width: 820px;
  margin: 0 auto;
}

.clear-board {
  position: relative;
  text-align: center;
  padding: 3rem 1.75rem;
  border-radius: 40px;
  background: var(--bg-elevated);
  border: 3px solid var(--line);
  box-shadow: var(--shadow-block);
  overflow: hidden;
}

.clear-board__pieces {
  position: absolute;
  inset: 0;
  pointer-events: none;
}

.mini-poly {
  position: absolute;
  width: 48px;
  height: 48px;
  border-radius: 14px;
  opacity: 0.85;
  box-shadow: inset 0 -4px 0 rgba(0, 0, 0, 0.15);
}

.mini-poly--red { background: var(--red); top: 18px; left: 24px; }
.mini-poly--blue { background: var(--blue); top: 28px; right: 32px; }
.mini-poly--green { background: var(--green); bottom: 24px; left: 40px; }
.mini-poly--yellow { background: var(--yellow); bottom: 32px; right: 28px; }

.clear-board__icon {
  margin: 0 auto 1rem;
  border-radius: 22px;
  box-shadow: 0 6px 0 rgba(26, 39, 68, 0.12);
}

.clear-board h2 {
  font-family: var(--font-display);
  font-size: clamp(1.6rem, 3vw, 2.2rem);
  margin: 0 0 0.65rem;
}

.clear-board > p {
  margin: 0 auto 1.5rem;
  max-width: 440px;
  color: var(--ink-muted);
}

.clear-board__cta {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem;
  justify-content: center;
}

/* ---------- FAQ ---------- */
.faq {
  padding: 2rem 1.25rem 5rem;
  max-width: 720px;
  margin: 0 auto;
}

.faq__list {
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
}

.faq__item {
  background: var(--bg-elevated);
  border-radius: 20px;
  border: 2px solid var(--line);
  padding: 0.35rem 1.15rem;
  box-shadow: 0 4px 0 rgba(26, 39, 68, 0.06);
}

.faq__item summary {
  font-family: var(--font-display);
  font-weight: 700;
  padding: 0.95rem 0;
  cursor: pointer;
  list-style: none;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
}

.faq__item summary::-webkit-details-marker {
  display: none;
}

.faq__item summary::after {
  content: "+";
  font-size: 1.35rem;
  color: var(--blue);
  flex-shrink: 0;
}

.faq__item[open] summary::after {
  content: "–";
}

.faq__item p {
  margin: 0 0 1rem;
  color: var(--ink-muted);
}

/* ---------- Footer ---------- */
.footer {
  padding: 2.5rem 1.25rem 3rem;
  border-top: 2px solid var(--line);
  background: color-mix(in srgb, var(--bg-elevated) 70%, transparent);
}

.footer__inner {
  max-width: 1000px;
  margin: 0 auto;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 1rem;
  text-align: center;
}

.footer__brand {
  display: inline-flex;
  align-items: center;
  gap: 0.55rem;
  font-family: var(--font-display);
  font-weight: 700;
}

.footer__brand img {
  border-radius: 10px;
}

.footer__links {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem 1.35rem;
  justify-content: center;
}

.footer__links a {
  font-weight: 600;
  color: var(--ink-muted);
  transition: color 0.2s;
}

.footer__links a:hover {
  color: var(--blue);
}

.footer__copy {
  margin: 0;
  font-size: 0.9rem;
  color: var(--ink-muted);
}

/* ---------- Modal ---------- */
.modal[hidden] {
  display: none;
}

.modal {
  position: fixed;
  inset: 0;
  z-index: 200;
  display: grid;
  place-items: center;
  padding: 1.25rem;
}

.modal__backdrop {
  position: absolute;
  inset: 0;
  background: rgba(18, 24, 42, 0.55);
  backdrop-filter: blur(4px);
  cursor: pointer;
}

.modal__panel {
  position: relative;
  width: min(100%, 420px);
  background: var(--bg-elevated);
  border-radius: 28px;
  padding: 2rem 1.75rem 1.75rem;
  text-align: center;
  border: 3px solid var(--line);
  box-shadow: var(--shadow-block);
  animation: modal-in 0.28s var(--ease);
}

.modal__close {
  position: absolute;
  top: 0.85rem;
  right: 0.85rem;
  width: 36px;
  height: 36px;
  border-radius: 12px;
  display: grid;
  place-items: center;
  color: var(--ink-muted);
  background: color-mix(in srgb, var(--blue) 10%, transparent);
}

.modal__icon {
  width: 64px;
  height: 64px;
  margin: 0 auto 1rem;
  border-radius: 20px;
  display: grid;
  place-items: center;
  background: linear-gradient(160deg, #5c9dff, var(--blue));
  color: #fff;
  box-shadow: 0 6px 0 var(--blue-deep);
}

.modal__panel h2 {
  font-family: var(--font-display);
  margin: 0 0 0.65rem;
}

.modal__panel p {
  margin: 0 0 1.35rem;
  color: var(--ink-muted);
}

@keyframes modal-in {
  from {
    opacity: 0;
    transform: translateY(12px) scale(0.96);
  }
  to {
    opacity: 1;
    transform: translateY(0) scale(1);
  }
}

/* ---------- Responsive ---------- */
@media (max-width: 960px) {
  .hero {
    grid-template-columns: 1fr;
    gap: 2rem;
  }

  .hero__phone {
    order: -1;
  }

  .phone-shell {
    width: min(100%, 260px);
  }

  .poly-bento {
    grid-template-columns: 1fr 1fr;
  }

  .bento-block--tall {
    grid-row: auto;
    min-height: 0;
  }

  .bento-block--wide {
    grid-column: span 2;
  }

  .escape-channel {
    grid-template-columns: 1fr;
    gap: 1.25rem;
  }

  .escape-step__arrow {
    display: none;
  }

  .gallery__tiles {
    grid-template-columns: 1fr;
    max-width: 320px;
    margin: 0 auto;
  }

  .screen-tile--a,
  .screen-tile--b,
  .screen-tile--c {
    transform: none;
  }
}

@media (max-width: 768px) {
  .stud-nav__burger {
    display: flex;
  }

  .stud-nav__links {
    position: absolute;
    top: calc(100% + 0.35rem);
    left: 1.25rem;
    right: 1.25rem;
    flex-direction: column;
    align-items: stretch;
    padding: 0.75rem;
    background: var(--bg-elevated);
    border-radius: 20px;
    border: 2px solid var(--line);
    box-shadow: var(--shadow-block);
    opacity: 0;
    pointer-events: none;
    transform: translateY(-8px);
    transition: opacity 0.2s, transform 0.2s;
  }

  .stud-nav__links.is-open {
    opacity: 1;
    pointer-events: auto;
    transform: translateY(0);
  }

  .stud-nav {
    position: sticky;
  }

  .stud-nav__inner {
    position: relative;
  }

  .exit-dock {
    display: none;
  }

  .polyomino-board {
    opacity: 0.45;
  }
}

@media (max-width: 560px) {
  .poly-bento {
    grid-template-columns: 1fr;
  }

  .bento-block--wide {
    grid-column: auto;
  }

  .hero__cta,
  .clear-board__cta {
    flex-direction: column;
  }

  .btn-exit,
  .btn-stud {
    width: 100%;
  }

  .stud-nav__name {
    display: none;
  }
}

/* Reduced motion */
@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto;
  }

  .polyomino-board,
  .poly--blue,
  .poly--green,
  .poly--yellow,
  .poly--white,
  .poly--red,
  .float-exit {
    animation: none !important;
  }

  *,
  *::before,
  *::after {
    transition-duration: 0.01ms !important;
    animation-duration: 0.01ms !important;
  }
}