@import url("https://fonts.googleapis.com/css2?family=IBM+Plex+Sans:wght@400;500;600;700&display=swap");

:root {
  --bg-950: #090b0f;
  --bg-900: #11141b;
  --bg-800: #1e2430;
  --text-100: #eef2f9;
  --text-300: #c9d1df;
  --text-500: #a9b2c3;
  --gold-500: #c8a24a;
  --gold-400: #d8b767;
  --gold-300: #e5cc8f;

  --surface: rgba(17, 20, 27, 0.94);
  --surface-alt: rgba(30, 36, 48, 0.93);
  --border: rgba(229, 204, 143, 0.24);
  --shadow-lg: 0 12px 24px rgba(0, 0, 0, 0.3);

  --ray-1: #ff7f7f;
  --ray-2: #ffd36d;
  --ray-3: #d5a7ff;
  --ray-ext: #e5cc8f;
  --axis: rgba(238, 242, 249, 0.52);

  --page-bg: radial-gradient(circle at 12% 9%, #222b3c 0%, #141925 40%, #090b0f 100%);
  --scene-bg: radial-gradient(circle at 12% 8%, rgba(217, 183, 103, 0.12), transparent 38%),
    linear-gradient(180deg, rgba(12, 16, 22, 0.98), rgba(9, 11, 15, 0.98));
  --hero-bg: linear-gradient(130deg, rgba(20, 24, 33, 0.95), rgba(10, 12, 18, 0.95));
  --hero-heading: #fff6df;
  --status-bg: rgba(30, 36, 48, 0.45);
  --legend-bg: rgba(17, 20, 27, 0.8);
  --btn-bg: linear-gradient(135deg, var(--gold-500), var(--gold-400));
  --btn-border: var(--gold-500);
  --btn-text: #2c1d06;
}

body[data-theme="light"] {
  --bg-950: #e9f4fb;
  --bg-900: #ffffff;
  --bg-800: #f1f9fd;
  --text-100: #123140;
  --text-300: #4b6570;
  --text-500: #70838b;
  --surface: #ffffff;
  --surface-alt: #f9fdff;
  --border: #c8dbe3;
  --shadow-lg: 0 10px 20px rgba(12, 54, 68, 0.12);
  --ray-ext: #6a5d38;
  --axis: rgba(18, 49, 64, 0.45);
  --page-bg:
    radial-gradient(1200px 700px at 8% 2%, rgba(19, 143, 176, 0.18), transparent 62%),
    radial-gradient(900px 600px at 92% 98%, rgba(220, 132, 32, 0.18), transparent 66%),
    linear-gradient(165deg, #e9f4fb, #fff4dd);
  --scene-bg: linear-gradient(180deg, #f8fcff, #f2f8fb);
  --hero-bg: linear-gradient(130deg, #ffffff, #f4fbff);
  --hero-heading: #123140;
  --status-bg: #f7fbfd;
  --legend-bg: rgba(255, 255, 255, 0.95);
  --btn-bg: linear-gradient(160deg, #0d839f, #0b5f77);
  --btn-border: #0a5d74;
  --btn-text: #ffffff;
}

* {
  box-sizing: border-box;
}

html,
body {
  margin: 0;
  min-height: 100%;
}

body {
  font-family: "IBM Plex Sans", "Segoe UI", sans-serif;
  color: var(--text-100);
  background: var(--page-bg);
  line-height: 1.3;
}

.bg-grid {
  position: fixed;
  inset: 0;
  z-index: -1;
  background-image: linear-gradient(rgba(229, 204, 143, 0.06) 1px, transparent 1px),
    linear-gradient(90deg, rgba(229, 204, 143, 0.06) 1px, transparent 1px);
  background-size: 42px 42px;
  mask-image: radial-gradient(circle at center, black 42%, transparent 95%);
}

body[data-theme="light"] .bg-grid {
  background-image: linear-gradient(rgba(15, 126, 155, 0.08) 1px, transparent 1px),
    linear-gradient(90deg, rgba(214, 123, 25, 0.08) 1px, transparent 1px);
}

h1,
h2,
h3 {
  margin: 0;
  font-family: "IBM Plex Sans", "Segoe UI", sans-serif;
  font-weight: 700;
}

.shell {
  width: min(1460px, calc(100% - 1rem));
  margin-inline: auto;
}

.hero {
  position: relative;
  margin-top: 0.7rem;
  border: 1px solid var(--border);
  border-left: 8px solid var(--gold-500);
  border-radius: 12px;
  padding: 0.85rem 1rem;
  background: var(--hero-bg);
  box-shadow: var(--shadow-lg);
}

body[data-theme="light"] .hero {
  border-left-color: #0f7e9b;
}

.theme-toggle-btn {
  position: absolute;
  top: 0.55rem;
  right: 0.7rem;
  border: 1px solid var(--btn-border);
  border-radius: 999px;
  padding: 0.34rem 0.7rem;
  background: var(--btn-bg);
  color: var(--btn-text);
  font: inherit;
  font-size: 0.8rem;
  font-weight: 700;
  cursor: pointer;
}

.kicker {
  margin: 0;
  font-size: 0.76rem;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  color: var(--gold-400);
  font-weight: 700;
}

body[data-theme="light"] .kicker {
  color: #095f76;
}

.hero h1 {
  font-size: clamp(1.5rem, 2.1vw, 2.1rem);
  color: var(--hero-heading);
  margin-top: 0.16rem;
}

.subtitle {
  margin: 0.22rem 0 0;
  color: var(--text-300);
  max-width: 72ch;
  padding-right: 10.4rem;
}

.app-layout {
  margin-top: 0.55rem;
  margin-bottom: 0.9rem;
  display: grid;
  gap: 0.65rem;
  grid-template-columns: repeat(12, minmax(0, 1fr));
}

.panel {
  border: 1px solid var(--border);
  border-radius: 12px;
  background: var(--surface);
  padding: 0.72rem 0.78rem;
  box-shadow: 0 8px 18px rgba(0, 0, 0, 0.2);
}

.controls-panel {
  grid-column: span 12;
}

.visual-panel {
  grid-column: span 8;
}

.metrics-panel {
  grid-column: span 4;
}

.controls-grid {
  margin-top: 0.42rem;
  display: grid;
  gap: 0.45rem;
  grid-template-columns: repeat(5, minmax(0, 1fr));
}

label,
.ray-toggles {
  display: flex;
  flex-direction: column;
  gap: 0.28rem;
  font-size: 0.84rem;
  color: var(--text-300);
}

input,
select,
button {
  font: inherit;
}

input[type="range"],
input[type="number"],
select {
  border: 1px solid var(--border);
  border-radius: 8px;
  background: var(--surface-alt);
  color: var(--text-100);
  padding: 0.42rem 0.52rem;
}

input[type="range"] {
  padding: 0;
  accent-color: var(--gold-500);
}

body[data-theme="light"] input[type="range"] {
  accent-color: #0f7e9b;
}

input[type="checkbox"] {
  accent-color: var(--gold-500);
}

body[data-theme="light"] input[type="checkbox"] {
  accent-color: #0f7e9b;
}

.ray-toggles {
  border: 1px solid var(--border);
  border-radius: 8px;
  background: rgba(30, 36, 48, 0.44);
  padding: 0.35rem 0.5rem;
}

body[data-theme="light"] .ray-toggles {
  background: #f6fbfd;
}

.ray-toggles legend {
  color: var(--gold-300);
  font-size: 0.78rem;
  padding: 0 0.18rem;
}

body[data-theme="light"] .ray-toggles legend {
  color: #095f76;
}

.toggle-label {
  flex-direction: row;
  align-items: center;
  gap: 0.42rem;
  font-size: 0.8rem;
}

button {
  border: 1px solid var(--btn-border);
  border-radius: 8px;
  background: var(--btn-bg);
  color: var(--btn-text);
  font-weight: 700;
  padding: 0.43rem 0.6rem;
  cursor: pointer;
}

button.ghost {
  background: rgba(200, 162, 74, 0.08);
  color: var(--text-100);
  border-color: var(--border);
}

body[data-theme="light"] button.ghost {
  background: #f6fbfd;
}

button:disabled {
  opacity: 0.55;
  cursor: not-allowed;
}

button:focus-visible,
input:focus-visible,
select:focus-visible {
  outline: 2px solid var(--gold-400);
  outline-offset: 1px;
}

body[data-theme="light"] button:focus-visible,
body[data-theme="light"] input:focus-visible,
body[data-theme="light"] select:focus-visible {
  outline-color: #ffad3b;
}

.button-row {
  margin-top: 0.48rem;
  display: flex;
  flex-wrap: wrap;
  gap: 0.4rem;
}

.hint,
.status,
.instruction {
  margin: 0.42rem 0 0;
  font-size: 0.83rem;
  color: var(--text-300);
}

.instruction {
  color: var(--text-100);
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 0.42rem 0.5rem;
  background: rgba(30, 36, 48, 0.4);
}

body[data-theme="light"] .instruction {
  background: #f7fbfd;
}

.scene {
  margin-top: 0.38rem;
  width: 100%;
  display: block;
  aspect-ratio: 1000 / 390;
  border: 1px solid var(--border);
  border-radius: 10px;
  background: var(--scene-bg);
}

.legend {
  display: flex;
  flex-wrap: wrap;
  gap: 0.34rem;
  margin-top: 0.42rem;
}

.legend-item {
  border: 1px solid var(--border);
  border-radius: 999px;
  padding: 0.16rem 0.5rem;
  font-size: 0.75rem;
  color: var(--text-100);
  background: var(--legend-bg);
}

.legend-item.ray1 {
  border-color: rgba(255, 127, 127, 0.8);
  color: #ffb1b1;
}

.legend-item.ray2 {
  border-color: rgba(255, 211, 109, 0.8);
  color: #ffe1a0;
}

.legend-item.ray3 {
  border-color: rgba(213, 167, 255, 0.8);
  color: #e4c8ff;
}

.legend-item.ext {
  border-style: dashed;
}

.step-list {
  margin: 0.38rem 0 0;
  padding-left: 1.05rem;
  color: var(--text-300);
  font-size: 0.82rem;
}

.step-list li + li {
  margin-top: 0.25rem;
}

.step-list li.active {
  color: var(--text-100);
  font-weight: 600;
}

.metrics-grid {
  margin-top: 0.4rem;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 0.28rem;
}

.metric-item {
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 0.34rem 0.42rem;
  background: rgba(30, 36, 48, 0.34);
}

body[data-theme="light"] .metric-item {
  background: #f7fbfd;
}

.metric-label {
  display: block;
  font-size: 0.68rem;
  color: var(--text-500);
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

.metric-value {
  display: block;
  margin-top: 0.1rem;
  font-size: 0.86rem;
  color: var(--text-100);
}

.practice-inline {
  margin-top: 0.52rem;
  border: 1px solid var(--border);
  border-radius: 9px;
  padding: 0.45rem 0.5rem;
  background: rgba(30, 36, 48, 0.34);
}

body[data-theme="light"] .practice-inline {
  background: #f7fbfd;
}

.practice-grid {
  margin-top: 0.34rem;
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 0.35rem;
}

.practice-field {
  display: grid;
  grid-template-rows: auto minmax(0, 1fr);
  gap: 0.28rem;
  align-content: start;
}

.practice-field input,
.practice-field select {
  width: 100%;
}

.practice-actions {
  margin-top: 0.34rem;
}

.status {
  padding: 0.42rem 0.5rem;
  border: 1px solid var(--border);
  border-radius: 8px;
  background: var(--status-bg);
}

.scene .axis {
  stroke: var(--axis);
  stroke-width: 2;
}

.scene .optic-line {
  stroke: #f3e3b6;
  stroke-width: 3.2;
  fill: none;
}

body[data-theme="light"] .scene .optic-line {
  stroke: #0f7e9b;
}

.scene .optic-fill {
  fill: rgba(216, 183, 103, 0.24);
  stroke: #f3e3b6;
  stroke-width: 1.6;
}

body[data-theme="light"] .scene .optic-fill {
  fill: rgba(15, 126, 155, 0.18);
  stroke: #0f7e9b;
}

.scene .optic-midline {
  stroke: rgba(229, 204, 143, 0.72);
  stroke-width: 1.5;
  stroke-dasharray: 4 5;
}

body[data-theme="light"] .scene .optic-midline {
  stroke: rgba(15, 126, 155, 0.7);
}

.scene .marker {
  stroke: rgba(229, 204, 143, 0.64);
  stroke-width: 1.3;
}

body[data-theme="light"] .scene .marker {
  stroke: rgba(18, 49, 64, 0.55);
}

.scene .marker-label,
.scene .value-label,
.scene .image-label {
  fill: var(--text-300);
  font-size: 12px;
  font-family: "IBM Plex Sans", sans-serif;
}

.scene .object,
.scene .image {
  stroke-width: 2.8;
}

.scene .object {
  stroke: #f8e7bc;
}

body[data-theme="light"] .scene .object {
  stroke: #0f7e9b;
}

.scene .image.real {
  stroke: #ffbb6b;
}

body[data-theme="light"] .scene .image.real {
  stroke: #d67b19;
}

.scene .image.virtual {
  stroke: #7fd7ff;
  stroke-dasharray: 6 4;
}

body[data-theme="light"] .scene .image.virtual {
  stroke: #236c8b;
}

.scene .ray {
  fill: none;
  stroke-width: 2.6;
  stroke-linecap: round;
}

.scene .ray.r1 {
  stroke: var(--ray-1);
}

.scene .ray.r2 {
  stroke: var(--ray-2);
}

.scene .ray.r3 {
  stroke: var(--ray-3);
}

.scene .ray.extension {
  stroke: var(--ray-ext);
  stroke-width: 1.9;
  stroke-dasharray: 8 6;
  opacity: 0.92;
}

.scene .ray.extra {
  stroke: #ead397;
  stroke-width: 1.8;
  opacity: 0.9;
}

body[data-theme="light"] .scene .ray.extra {
  stroke: #0a6d88;
  opacity: 0.65;
}

.scene .guide {
  stroke: rgba(229, 204, 143, 0.22);
  stroke-width: 1;
  stroke-dasharray: 4 6;
}

body[data-theme="light"] .scene .guide {
  stroke: rgba(18, 49, 64, 0.2);
}

.scene .smiley-image {
  pointer-events: none;
}

.scene .handle {
  fill: rgba(216, 183, 103, 0.2);
  stroke: var(--gold-300);
  stroke-width: 1.8;
  cursor: pointer;
}

body[data-theme="light"] .scene .handle {
  fill: rgba(15, 126, 155, 0.18);
  stroke: #0f7e9b;
}

@media (max-width: 1180px) {
  .controls-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .visual-panel,
  .metrics-panel {
    grid-column: span 12;
  }

  .subtitle {
    padding-right: 0;
  }

  .practice-grid {
    grid-template-columns: 1fr;
  }
}

@media (max-width: 760px) {
  .shell {
    width: min(1460px, calc(100% - 0.6rem));
  }

  .controls-grid {
    grid-template-columns: 1fr;
  }

  .button-row {
    display: grid;
    grid-template-columns: 1fr 1fr;
  }

  .metrics-grid {
    grid-template-columns: 1fr;
  }

  .theme-toggle-btn {
    position: static;
    margin-bottom: 0.4rem;
  }
}