:root {
  --bg-main: #07111f;
  --bg-card: rgba(11, 24, 40, 0.78);
  --bg-card-strong: rgba(8, 18, 31, 0.96);
  --line-soft: rgba(128, 187, 255, 0.22);
  --line-strong: rgba(128, 187, 255, 0.55);
  --text-main: #e9f1ff;
  --text-dim: #9cb4d1;
  --accent-cyan: #67f4d4;
  --accent-amber: #ffc267;
  --accent-red: #ff7965;
  --radius-lg: 24px;
  --radius-md: 16px;
}

* {
  box-sizing: border-box;
}

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

body {
  font-family: "Chakra Petch", "Avenir Next", "Segoe UI", sans-serif;
  color: var(--text-main);
  background:
    radial-gradient(1200px 800px at 10% -20%, rgba(103, 244, 212, 0.24), transparent 60%),
    radial-gradient(900px 700px at 110% 10%, rgba(255, 194, 103, 0.22), transparent 62%),
    linear-gradient(145deg, #040b14 0%, #07111f 45%, #0b1625 100%);
  overflow-x: hidden;
}

.ambient-lights {
  position: fixed;
  inset: 0;
  pointer-events: none;
  background-image:
    linear-gradient(to right, rgba(255, 255, 255, 0.03) 1px, transparent 1px),
    linear-gradient(to bottom, rgba(255, 255, 255, 0.03) 1px, transparent 1px);
  background-size: 40px 40px;
  mask-image: radial-gradient(circle at center, black 24%, transparent 88%);
  opacity: 0.45;
}

.shell {
  width: min(1100px, 100% - 2.5rem);
  margin: 2.2rem auto 2rem;
  display: grid;
  grid-template-columns: 1fr;
  gap: 1.1rem;
  position: relative;
  z-index: 2;
}

.hero {
  border: 1px solid var(--line-soft);
  border-radius: var(--radius-lg);
  background: linear-gradient(180deg, rgba(10, 22, 37, 0.82), rgba(7, 17, 31, 0.88));
  padding: 1.4rem 1.5rem;
  box-shadow: 0 24px 70px rgba(0, 0, 0, 0.45);
  animation: rise-in 0.8s ease-out;
}

.eyebrow {
  margin: 0 0 0.4rem;
  text-transform: uppercase;
  letter-spacing: 0.22em;
  color: var(--accent-cyan);
  font-size: 0.78rem;
}

.hero h1 {
  margin: 0;
  font-size: clamp(1.8rem, 2.7vw, 2.85rem);
  letter-spacing: 0.04em;
}

.subtitle {
  margin: 0.55rem 0 0;
  color: var(--text-dim);
  max-width: 58ch;
}

.tab-strip {
  grid-column: 1 / -1;
  display: flex;
  gap: 0.55rem;
  flex-wrap: wrap;
}

.tab-btn {
  appearance: none;
  border: 1px solid var(--line-soft);
  border-radius: 999px;
  padding: 0.58rem 1rem;
  background: rgba(8, 18, 31, 0.72);
  color: var(--text-dim);
  cursor: pointer;
  font-family: "Space Mono", Menlo, Consolas, monospace;
  letter-spacing: 0.03em;
  font-size: 0.82rem;
  transition: transform 0.2s ease, border-color 0.2s ease, color 0.2s ease, background 0.2s ease;
}

.tab-btn:hover {
  transform: translateY(-1px);
  border-color: var(--line-strong);
  color: var(--text-main);
}

.tab-btn.is-active {
  background: linear-gradient(120deg, rgba(103, 244, 212, 0.17), rgba(255, 194, 103, 0.14));
  border-color: var(--line-strong);
  color: var(--text-main);
}

.panel {
  border: 1px solid var(--line-soft);
  border-radius: var(--radius-lg);
  background: var(--bg-card);
  backdrop-filter: blur(14px);
  box-shadow: 0 22px 56px rgba(0, 0, 0, 0.36);
  animation: rise-in 0.95s ease-out;
}

.controls-panel {
  padding: 1rem;
}

.mode-panel {
  display: none;
}

.mode-panel.is-active {
  display: block;
}

.drop-zone {
  display: block;
  border-radius: var(--radius-md);
  border: 1px dashed rgba(255, 255, 255, 0.34);
  padding: 1.2rem 1rem;
  background:
    linear-gradient(120deg, rgba(103, 244, 212, 0.1), rgba(255, 194, 103, 0.07)),
    rgba(8, 17, 28, 0.84);
  cursor: pointer;
  transition: transform 0.24s ease, border-color 0.24s ease, background 0.24s ease;
}

.drop-zone:hover,
.drop-zone.is-active {
  transform: translateY(-2px);
  border-color: var(--line-strong);
  background:
    linear-gradient(120deg, rgba(103, 244, 212, 0.16), rgba(255, 121, 101, 0.09)),
    rgba(9, 19, 31, 0.96);
}

.drop-zone input {
  display: none;
}

.drop-title {
  display: block;
  font-weight: 700;
  font-size: 1.05rem;
}

.drop-copy {
  display: block;
  margin-top: 0.38rem;
  color: var(--text-dim);
  font-size: 0.95rem;
}

.diff-drop-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 0.72rem;
}

.meta-grid {
  margin-top: 1rem;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 0.7rem;
}

.meta-item {
  border: 1px solid rgba(255, 255, 255, 0.14);
  border-radius: 12px;
  padding: 0.72rem 0.74rem;
  background: rgba(8, 18, 30, 0.68);
}

.meta-label {
  margin: 0;
  color: var(--text-dim);
  font-size: 0.78rem;
  text-transform: uppercase;
  letter-spacing: 0.08em;
}

.meta-value {
  margin: 0.3rem 0 0;
  font-family: "Space Mono", Menlo, Consolas, monospace;
  font-size: 0.92rem;
  color: var(--text-main);
  word-break: break-word;
}

#audioPlayer {
  width: 100%;
  margin-top: 1rem;
  filter: saturate(1.1) contrast(1.02);
}

.chart-panel {
  padding: 1rem;
}

.canvas-wrap {
  position: relative;
  border-radius: var(--radius-md);
  overflow: hidden;
  border: 1px solid rgba(255, 255, 255, 0.14);
  background: var(--bg-card-strong);
  min-height: min(56vh, 420px);
}

#spectrumCanvas {
  width: 100%;
  height: min(56vh, 420px);
  display: block;
}

.canvas-placeholder {
  position: absolute;
  inset: auto 0 1rem;
  text-align: center;
  margin: 0;
  font-family: "Space Mono", Menlo, Consolas, monospace;
  color: rgba(233, 241, 255, 0.82);
  letter-spacing: 0.04em;
}

.site-footer {
  grid-column: 1 / -1;
  padding: 0.9rem 1rem;
}

.footer-links {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 0.8rem 1.1rem;
}

.footer-links a {
  color: var(--accent-cyan);
  text-decoration: none;
  border-bottom: 1px solid rgba(103, 244, 212, 0.38);
  font-family: "Space Mono", Menlo, Consolas, monospace;
  font-size: 0.84rem;
  letter-spacing: 0.03em;
}

.footer-links a:hover {
  color: #b2fff0;
  border-bottom-color: rgba(178, 255, 240, 0.75);
}

.footer-section {
  border: 1px solid rgba(255, 255, 255, 0.14);
  border-radius: 12px;
  background: rgba(8, 18, 30, 0.65);
  padding: 0.82rem 0.88rem;
}

.footer-section h2 {
  margin: 0;
  font-size: 0.82rem;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--text-dim);
}

.footer-section p {
  margin: 0.48rem 0 0;
  color: var(--text-main);
  line-height: 1.5;
  font-size: 0.92rem;
}

.contact-copy {
  margin-bottom: 0.5rem;
}

.contact-form {
  margin-top: 0.55rem;
  display: grid;
  gap: 0.42rem;
}

.contact-label {
  font-size: 0.74rem;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--text-dim);
}

.contact-input {
  width: 100%;
  border: 1px solid rgba(255, 255, 255, 0.18);
  border-radius: 9px;
  background: rgba(7, 15, 26, 0.85);
  color: var(--text-main);
  padding: 0.56rem 0.62rem;
  font: inherit;
}

.contact-input:focus {
  outline: none;
  border-color: var(--line-strong);
  box-shadow: 0 0 0 2px rgba(103, 244, 212, 0.22);
}

.contact-textarea {
  resize: vertical;
  min-height: 96px;
}

.contact-submit {
  margin-top: 0.35rem;
  border: 1px solid var(--line-strong);
  border-radius: 10px;
  background: linear-gradient(120deg, rgba(103, 244, 212, 0.18), rgba(255, 194, 103, 0.16));
  color: var(--text-main);
  padding: 0.58rem 0.72rem;
  cursor: pointer;
  font-family: "Space Mono", Menlo, Consolas, monospace;
  font-size: 0.82rem;
  letter-spacing: 0.03em;
}

.contact-submit:disabled {
  opacity: 0.55;
  cursor: not-allowed;
}

.contact-status {
  min-height: 1.2em;
  margin: 0.3rem 0 0;
  color: var(--accent-cyan);
  font-size: 0.82rem;
}

.contact-status.is-error {
  color: var(--accent-red);
}

.contact-modal {
  position: fixed;
  inset: 0;
  z-index: 20;
  display: grid;
  place-items: center;
  padding: 1rem;
}

.contact-modal[hidden] {
  display: none;
}

.contact-modal-backdrop {
  position: absolute;
  inset: 0;
  background: rgba(3, 8, 14, 0.74);
  backdrop-filter: blur(4px);
}

.contact-modal-panel {
  position: relative;
  z-index: 1;
  width: min(520px, 100%);
  border: 1px solid var(--line-soft);
  border-radius: 16px;
  background: rgba(8, 18, 30, 0.95);
  box-shadow: 0 28px 70px rgba(0, 0, 0, 0.55);
  padding: 0.92rem;
}

.contact-modal-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 0.6rem;
  margin-bottom: 0.25rem;
}

.contact-modal-header h2 {
  margin: 0;
  font-size: 1.05rem;
  letter-spacing: 0.03em;
}

.contact-modal-close {
  border: 1px solid rgba(255, 255, 255, 0.25);
  border-radius: 8px;
  background: rgba(8, 18, 31, 0.8);
  color: var(--text-main);
  cursor: pointer;
  padding: 0.34rem 0.55rem;
  font-family: "Space Mono", Menlo, Consolas, monospace;
  font-size: 0.75rem;
  letter-spacing: 0.03em;
}

.contact-modal-close:hover {
  border-color: var(--line-strong);
}

.footer-section a {
  color: var(--accent-cyan);
  text-decoration: none;
  border-bottom: 1px solid rgba(103, 244, 212, 0.38);
}

.footer-section a:hover {
  color: #b2fff0;
  border-bottom-color: rgba(178, 255, 240, 0.75);
}

.legal-shell {
  width: min(900px, 100% - 2.5rem);
}

.legal-nav {
  display: flex;
  flex-wrap: wrap;
  gap: 0.55rem;
}

.legal-link {
  display: inline-block;
  border: 1px solid var(--line-soft);
  border-radius: 999px;
  padding: 0.5rem 0.9rem;
  background: rgba(8, 18, 31, 0.72);
  color: var(--text-dim);
  text-decoration: none;
  font-family: "Space Mono", Menlo, Consolas, monospace;
  font-size: 0.8rem;
  letter-spacing: 0.03em;
  transition: transform 0.2s ease, border-color 0.2s ease, color 0.2s ease;
}

.legal-link:hover {
  transform: translateY(-1px);
  border-color: var(--line-strong);
  color: var(--text-main);
}

.legal-link.is-active {
  border-color: var(--line-strong);
  background: linear-gradient(120deg, rgba(103, 244, 212, 0.17), rgba(255, 194, 103, 0.14));
  color: var(--text-main);
}

.legal-panel {
  padding: 1.1rem 1.15rem;
}

.legal-panel h2 {
  margin: 0.3rem 0 0.3rem;
  font-size: 1.02rem;
  letter-spacing: 0.03em;
}

.legal-panel p {
  margin: 0 0 1rem;
  color: var(--text-main);
  line-height: 1.58;
}

.legal-panel a {
  color: var(--accent-cyan);
  text-decoration: none;
  border-bottom: 1px solid rgba(103, 244, 212, 0.38);
}

.legal-panel a:hover {
  color: #b2fff0;
  border-bottom-color: rgba(178, 255, 240, 0.75);
}

@keyframes rise-in {
  from {
    transform: translateY(14px);
    opacity: 0;
  }
  to {
    transform: translateY(0);
    opacity: 1;
  }
}

@media (min-width: 860px) {
  .shell {
    margin-top: 2.6rem;
    grid-template-columns: minmax(320px, 0.95fr) minmax(460px, 1.5fr);
    grid-template-areas:
      "hero hero"
      "tabs tabs"
      "controls chart";
    gap: 1.1rem;
  }

  .tab-strip {
    grid-area: tabs;
  }

  .hero {
    grid-area: hero;
    padding: 1.65rem 1.7rem;
  }

  .controls-panel {
    grid-area: controls;
    height: fit-content;
    position: sticky;
    top: 1.2rem;
  }

  .chart-panel {
    grid-area: chart;
  }

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

  .diff-drop-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .site-footer {
    padding: 0.95rem 1.15rem;
  }

  .legal-shell {
    grid-template-columns: 1fr;
    grid-template-areas: none;
  }

  .legal-shell .hero {
    grid-area: auto;
  }
}