:root {
  --track-black: #0d1118;
  --track-black-soft: #171e2a;
  --nhra-red: #cf1f2e;
  --nhra-red-bright: #f44336;
  --nhra-blue: #0e4ea8;
  --nhra-blue-bright: #1d74da;
  --flag-white: #f6f8fb;
  --line-silver: #c5cedb;
  --text-main: #ecf2ff;
  --text-soft: #c7d2e8;
  --panel: rgba(17, 26, 39, 0.88);
  --panel-alt: rgba(22, 34, 52, 0.92);
  --shadow: 0 20px 45px rgba(4, 8, 15, 0.48);
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  min-height: 100vh;
  font-family: "Rajdhani", "Segoe UI", sans-serif;
  color: var(--text-main);
  background:
    linear-gradient(120deg, rgba(207, 31, 46, 0.2) 0 21%, transparent 21% 100%),
    linear-gradient(300deg, rgba(14, 78, 168, 0.22) 0 24%, transparent 24% 100%),
    repeating-linear-gradient(135deg, rgba(255, 255, 255, 0.03) 0 14px, rgba(255, 255, 255, 0) 14px 28px),
    linear-gradient(165deg, #070b12 0%, #111827 52%, #1a263a 100%);
  overflow-x: hidden;
}

.bg-shape {
  position: fixed;
  z-index: -1;
  filter: blur(0.5px);
  opacity: 0.52;
}

.bg-shape-a {
  width: min(44vw, 620px);
  height: min(44vw, 620px);
  right: -15vw;
  top: 7vh;
  border-radius: 45% 55% 66% 34% / 45% 35% 65% 55%;
  background: radial-gradient(circle at 35% 30%, rgba(244, 67, 54, 0.95), rgba(156, 21, 34, 0.15) 67%);
  animation: driftA 11s ease-in-out infinite alternate;
}

.bg-shape-b {
  width: min(36vw, 460px);
  height: min(36vw, 460px);
  left: -10vw;
  bottom: -12vh;
  border-radius: 58% 42% 36% 64% / 54% 62% 38% 46%;
  background: radial-gradient(circle at 65% 45%, rgba(29, 116, 218, 0.9), rgba(15, 52, 106, 0.1) 70%);
  animation: driftB 10s ease-in-out infinite alternate;
}

.layout {
  max-width: 1180px;
  margin: 0 auto;
  padding: 2.4rem 1rem 2.6rem;
  display: grid;
  grid-template-columns: 1fr;
  gap: 1rem;
}

.card {
  position: relative;
  isolation: isolate;
  background: linear-gradient(160deg, var(--panel) 0%, var(--panel-alt) 100%);
  border: 1px solid rgba(197, 206, 219, 0.26);
  border-radius: 0.55rem;
  box-shadow: var(--shadow);
  padding: 1.2rem;
  clip-path: polygon(0 0, calc(100% - 22px) 0, 100% 22px, 100% 100%, 0 100%);
  animation: reveal 0.48s ease both;
}

.card::before {
  content: "";
  position: absolute;
  inset: 0;
  z-index: -1;
  background:
    linear-gradient(95deg, rgba(207, 31, 46, 0.45), transparent 28%),
    linear-gradient(275deg, rgba(29, 116, 218, 0.42), transparent 30%);
  opacity: 0.34;
}

.card::after {
  content: "";
  position: absolute;
  right: 0;
  top: 0;
  width: 22px;
  height: 22px;
  background: linear-gradient(140deg, var(--nhra-red) 0%, var(--nhra-blue) 100%);
}

.results-card {
  animation-delay: 0.18s;
}

.eyebrow {
  margin: 0;
  font-family: "Teko", sans-serif;
  font-size: 1.15rem;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--flag-white);
  text-shadow: 0 0 12px rgba(207, 31, 46, 0.45);
}

h1,
h2,
h3 {
  margin: 0;
  font-family: "Teko", sans-serif;
  line-height: 0.98;
  letter-spacing: 0.02em;
}

h1 {
  margin-top: 0.2rem;
  font-size: clamp(2.2rem, 4.8vw, 3.5rem);
  color: var(--flag-white);
  text-transform: uppercase;
}

h2 {
  font-size: clamp(1.85rem, 3.2vw, 2.4rem);
  margin-bottom: 0.65rem;
  text-transform: uppercase;
  color: var(--flag-white);
}

h3 {
  font-size: 1.45rem;
  margin-bottom: 0.2rem;
  color: #f2f6ff;
}

.intro-text {
  color: var(--text-soft);
  font-size: 1.03rem;
  line-height: 1.28;
  max-width: 62ch;
}

.instruction-note {
  margin: 0.2rem 0 0.5rem;
  color: #ffd5d8;
  font-weight: 700;
  line-height: 1.2;
  border-left: 3px solid var(--nhra-red-bright);
  padding-left: 0.55rem;
}

.instruction-links {
  margin: 0.1rem 0 0.55rem;
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem 0.9rem;
}

.instruction-links a {
  color: #8ab6ff;
  text-decoration: underline;
  text-underline-offset: 2px;
  font-weight: 700;
}

.instruction-links a:hover {
  color: #b5d0ff;
}

.calc-form {
  margin-top: 0.9rem;
  display: grid;
  gap: 0.72rem;
}

.input-layout {
  margin-top: 0.9rem;
  display: grid;
  grid-template-columns: 1fr;
  gap: 0.9rem;
}

.example-label {
  margin: 0;
  font-family: "Teko", sans-serif;
  font-size: 1.35rem;
  letter-spacing: 0.04em;
  color: #f2f6ff;
}

.combo-figure {
  margin: 0;
  width: 100%;
  border: 1px solid rgba(195, 209, 235, 0.26);
  border-radius: 0.45rem;
  background: rgba(8, 13, 21, 0.5);
  padding: 0.3rem;
}

.combo-image {
  display: block;
  width: 100%;
  height: auto;
  border-radius: 0.25rem;
}

.input-panel {
  width: 100%;
}

.input-panel .calc-form {
  margin-top: 0;
}

.field {
  display: grid;
  gap: 0.35rem;
  font-weight: 700;
  color: #e6eeff;
  letter-spacing: 0.01em;
}

.field input,
.field select {
  width: 100%;
  border: 1px solid rgba(178, 196, 228, 0.4);
  border-radius: 0.42rem;
  padding: 0.75rem 0.85rem;
  font-size: 1rem;
  font-family: inherit;
  font-weight: 600;
  color: #f3f7ff;
  background: rgba(8, 13, 21, 0.58);
  transition: border-color 0.2s ease, box-shadow 0.2s ease, transform 0.2s ease;
}

.field input:focus,
.field select:focus {
  outline: none;
  border-color: #8ab6ff;
  box-shadow: 0 0 0 3px rgba(44, 116, 217, 0.26);
  transform: translateY(-1px);
}

.btn {
  border: 0;
  border-radius: 0.42rem;
  font-family: "Teko", sans-serif;
  letter-spacing: 0.08em;
  font-size: 1.4rem;
  font-weight: 700;
  color: #fff;
  padding: 0.6rem 1rem;
  background:
    linear-gradient(90deg, var(--nhra-red) 0 52%, var(--nhra-blue) 52% 100%),
    linear-gradient(145deg, var(--nhra-red-bright), var(--nhra-blue-bright));
  box-shadow: 0 10px 25px rgba(6, 9, 15, 0.38);
  cursor: pointer;
  transition: transform 0.16s ease, filter 0.16s ease, box-shadow 0.16s ease;
}

.btn:hover {
  filter: brightness(1.05);
  box-shadow: 0 14px 28px rgba(6, 9, 15, 0.5);
}

.btn:active {
  transform: translateY(1px) scale(0.99);
}

.form-error {
  min-height: 1.3rem;
  margin-top: 0.55rem;
  color: #ff858d;
  font-weight: 700;
}

.disclaimer {
  margin: 0.5rem 0 0;
  padding-top: 0.55rem;
  border-top: 1px solid rgba(197, 206, 219, 0.24);
  color: #c7d2e8;
  font-size: 0.9rem;
  line-height: 1.2;
}

.empty-state {
  color: var(--text-soft);
  border: 1px dashed rgba(185, 199, 227, 0.35);
  border-radius: 0.45rem;
  padding: 0.7rem;
}

.hidden {
  display: none;
}

.stat-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 0.7rem;
}

.stat {
  border: 1px solid rgba(195, 209, 235, 0.24);
  border-radius: 0.45rem;
  padding: 0.62rem 0.74rem;
  background:
    linear-gradient(92deg, rgba(207, 31, 46, 0.18) 0 7px, rgba(255, 255, 255, 0.03) 7px 100%),
    rgba(20, 30, 45, 0.8);
}

.stat p {
  margin: 0;
  font-family: "Teko", sans-serif;
  font-size: 1.55rem;
  line-height: 0.95;
  font-weight: 700;
  color: #ffffff;
  letter-spacing: 0.02em;
}

.class-section {
  margin-top: 0.85rem;
}

.class-note {
  margin: 0.1rem 0 0.65rem;
  color: var(--text-soft);
}

.class-list {
  display: grid;
  gap: 0.48rem;
}

.class-disclaimers {
  margin-top: 0.6rem;
  display: grid;
  gap: 0.35rem;
}

.class-disclaimer-item {
  margin: 0;
  padding: 0.45rem 0.55rem;
  border-left: 3px solid var(--nhra-red-bright);
  background: rgba(207, 31, 46, 0.1);
  color: #ffd8dc;
  font-size: 0.92rem;
  line-height: 1.2;
}

.class-item {
  position: relative;
  border: 1px solid rgba(195, 209, 235, 0.26);
  border-radius: 0.4rem;
  background: linear-gradient(92deg, rgba(14, 78, 168, 0.18) 0 6px, rgba(255, 255, 255, 0.02) 6px 100%);
  padding: 0.62rem 0.76rem;
}

.class-item strong {
  font-family: "Teko", sans-serif;
  font-size: 1.45rem;
  line-height: 0.92;
  letter-spacing: 0.04em;
  color: var(--flag-white);
}

.class-meta {
  color: var(--text-soft);
  font-size: 0.96rem;
  font-weight: 600;
}

@media (min-width: 860px) {
  .layout {
    grid-template-columns: 1.05fr 0.95fr;
    align-items: start;
    padding: 2.9rem 1.5rem 3.2rem;
  }

  .card {
    padding: 1.5rem;
  }

  .stat-grid {
    grid-template-columns: repeat(3, 1fr);
  }
}

@media (max-width: 420px) {
  .card {
    padding: 1rem;
  }

  h1 {
    font-size: clamp(2rem, 9.5vw, 2.4rem);
  }

  .btn {
    font-size: 1.22rem;
  }
}

@keyframes reveal {
  from {
    opacity: 0;
    transform: translateY(12px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

@keyframes driftA {
  from {
    transform: translate(-3%, -2%) rotate(0deg);
  }
  to {
    transform: translate(2%, 2%) rotate(7deg);
  }
}

@keyframes driftB {
  from {
    transform: translate(3%, 0%) rotate(0deg);
  }
  to {
    transform: translate(-2%, 2%) rotate(-8deg);
  }
}