:root {
  /* =========================
   *  Color System
   * ========================= */
  --color-background: #050812;
  --color-surface: #0c111c;
  --color-surface-elevated: #141a28;
  --color-text: #f7f7fb;
  --color-text-muted: #a5aec4;
  --color-primary: #f74c2f; /* energetic accent */
  --color-primary-soft: rgba(247, 76, 47, 0.08);
  --color-primary-strong: #ff6245;
  --color-success: #2ecc71;
  --color-warning: #f1c40f;
  --color-danger: #e74c3c;

  --gray-50: #f8fafc;
  --gray-100: #e2e8f0;
  --gray-200: #cbd5f5;
  --gray-300: #94a3b8;
  --gray-400: #64748b;
  --gray-500: #475569;
  --gray-600: #334155;
  --gray-700: #1e293b;
  --gray-800: #0f172a;
  --gray-900: #020617;

  /* =========================
   *  Typography
   * ========================= */
  --font-sans: system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto,
    "Helvetica Neue", Arial, "Noto Sans", sans-serif, "Apple Color Emoji",
    "Segoe UI Emoji", "Segoe UI Symbol", "Noto Color Emoji";
  --font-display: "Poppins", system-ui, -apple-system, BlinkMacSystemFont,
    "Segoe UI", sans-serif;

  --font-size-xs: 0.75rem;   /* 12px */
  --font-size-sm: 0.875rem;  /* 14px */
  --font-size-base: 1rem;    /* 16px */
  --font-size-lg: 1.125rem;  /* 18px */
  --font-size-xl: 1.25rem;   /* 20px */
  --font-size-2xl: 1.5rem;   /* 24px */
  --font-size-3xl: 1.875rem; /* 30px */
  --font-size-4xl: 2.25rem;  /* 36px */

  --line-height-tight: 1.2;
  --line-height-snug: 1.35;
  --line-height-normal: 1.5;
  --line-height-relaxed: 1.7;

  /* =========================
   *  Spacing Scale (px)
   * ========================= */
  --space-0: 0;
  --space-1: 4px;
  --space-2: 8px;
  --space-3: 12px;
  --space-4: 16px;
  --space-5: 20px;
  --space-6: 24px;
  --space-7: 28px;
  --space-8: 32px;
  --space-9: 36px;
  --space-10: 40px;
  --space-12: 48px;
  --space-14: 56px;
  --space-16: 64px;
  --space-20: 80px;
  --space-24: 96px;

  /* =========================
   *  Radius & Shadows
   * ========================= */
  --radius-sm: 4px;
  --radius-md: 8px;
  --radius-lg: 12px;
  --radius-xl: 18px;
  --radius-full: 999px;

  --shadow-soft: 0 10px 30px rgba(0, 0, 0, 0.35);
  --shadow-strong: 0 22px 60px rgba(0, 0, 0, 0.6);

  /* =========================
   *  Transitions & Motion
   * ========================= */
  --transition-fast: 120ms ease-out;
  --transition-base: 180ms ease-out;
  --transition-slow: 260ms ease-out;
}

/* =========================
 *  Reset & Normalize
 * ========================= */

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

html,
body {
  margin: 0;
  padding: 0;
}

html {
  scroll-behavior: smooth;
  text-size-adjust: 100%;
}

body {
  min-height: 100vh;
}

img,
picture,
video,
canvas,
svg {
  display: block;
  max-width: 100%;
}

img {
  height: auto;
}

button,
input,
select,
textarea {
  font: inherit;
  color: inherit;
}

ul,
ol {
  margin: 0;
  padding: 0;
}

h1,
h2,
h3,
h4,
h5,
h6,
p,
figure {
  margin: 0;
}

button {
  border: none;
  background: none;
  padding: 0;
}

:focus:not(:focus-visible) {
  outline: none;
}

/* =========================
 *  Base Styles
 * ========================= */

body {
  font-family: var(--font-sans);
  font-size: var(--font-size-base);
  line-height: var(--line-height-normal);
  color: var(--color-text);
  background: radial-gradient(circle at top left, #151a2b 0, #050812 55%, #000 100%);
  -webkit-font-smoothing: antialiased;
}

h1,
h2,
h3,
h4,
h5,
h6 {
  font-family: var(--font-display);
  font-weight: 600;
  line-height: var(--line-height-tight);
  color: var(--color-text);
}

h1 {
  font-size: var(--font-size-4xl);
  letter-spacing: 0.02em;
}

h2 {
  font-size: var(--font-size-3xl);
}

h3 {
  font-size: var(--font-size-2xl);
}

h4 {
  font-size: var(--font-size-xl);
}

h5 {
  font-size: var(--font-size-lg);
}

h6 {
  font-size: var(--font-size-base);
  text-transform: uppercase;
  letter-spacing: 0.12em;
}

p {
  margin-top: 0;
  margin-bottom: var(--space-4);
  color: var(--color-text-muted);
}

a {
  color: var(--color-primary);
  text-decoration: none;
  transition: color var(--transition-base);
}

a:hover {
  color: var(--color-primary-strong);
}

a:focus-visible {
  outline: 2px solid var(--color-primary);
  outline-offset: 3px;
}

strong {
  font-weight: 600;
}

hr {
  border: none;
  border-top: 1px solid rgba(255, 255, 255, 0.06);
  margin: var(--space-8) 0;
}

/* =========================
 *  Utilities
 * ========================= */

.container {
  width: 100%;
  margin-left: auto;
  margin-right: auto;
  padding-left: var(--space-4);
  padding-right: var(--space-4);
  max-width: 1200px;
}

@media (min-width: 1280px) {
  .container {
    max-width: 1280px;
  }
}

.flex {
  display: flex;
}

.inline-flex {
  display: inline-flex;
}

.flex-center {
  display: flex;
  align-items: center;
  justify-content: center;
}

.flex-between {
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.flex-col {
  display: flex;
  flex-direction: column;
}

.grid {
  display: grid;
}

.grid-2 {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: var(--space-6);
}

@media (max-width: 768px) {
  .grid-2 {
    grid-template-columns: minmax(0, 1fr);
  }
}

.text-center {
  text-align: center;
}

.text-right {
  text-align: right;
}

.mt-0 { margin-top: 0; }
.mt-4 { margin-top: var(--space-4); }
.mt-8 { margin-top: var(--space-8); }
.mb-0 { margin-bottom: 0; }
.mb-4 { margin-bottom: var(--space-4); }
.mb-8 { margin-bottom: var(--space-8); }

.pt-8 { padding-top: var(--space-8); }
.pb-8 { padding-bottom: var(--space-8); }
.pt-16 { padding-top: var(--space-16); }
.pb-16 { padding-bottom: var(--space-16); }

.section {
  padding-top: var(--space-16);
  padding-bottom: var(--space-16);
}

.section--alt {
  background: radial-gradient(circle at top right, #1c2135 0, #050812 60%);
}

/* Screen reader only */
.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}

/* =========================
 *  Components
 * ========================= */

/* Buttons */

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.4rem;
  padding: 0.7rem 1.4rem;
  border-radius: var(--radius-full);
  font-size: var(--font-size-sm);
  font-weight: 600;
  letter-spacing: 0.04em;
  text-transform: uppercase;
  border: 1px solid transparent;
  cursor: pointer;
  transition:
    background-color var(--transition-base),
    color var(--transition-base),
    border-color var(--transition-base),
    box-shadow var(--transition-base),
    transform var(--transition-fast);
}

.btn-primary {
  background: linear-gradient(135deg, var(--color-primary), var(--color-primary-strong));
  color: #fff !important;
  box-shadow: 0 14px 35px rgba(247, 76, 47, 0.35);
}

.btn-primary:hover {
  transform: translateY(-1px);
  box-shadow: 0 18px 45px rgba(247, 76, 47, 0.5);
}

.btn-outline {
  background: transparent;
  color: var(--color-text);
  border-color: rgba(255, 255, 255, 0.18);
}

.btn-outline:hover {
  background: rgba(255, 255, 255, 0.04);
}

.btn-ghost {
  background: rgba(255, 255, 255, 0.02);
  color: var(--color-text);
}

.btn-ghost:hover {
  background: rgba(255, 255, 255, 0.06);
}

.btn:disabled,
.btn[aria-disabled="true"] {
  opacity: 0.5;
  cursor: not-allowed;
  box-shadow: none;
  transform: none;
}

.btn:focus-visible {
  outline: 2px solid var(--color-primary-strong);
  outline-offset: 3px;
}

/* Inputs & Forms */

.input,
.select,
.textarea {
  width: 100%;
  padding: 0.7rem 0.9rem;
  border-radius: var(--radius-md);
  border: 1px solid rgba(255, 255, 255, 0.16);
  background-color: rgba(6, 11, 25, 0.9);
  color: var(--color-text);
  font-size: var(--font-size-sm);
  line-height: 1.4;
  transition:
    border-color var(--transition-base),
    box-shadow var(--transition-base),
    background-color var(--transition-base);
}

.input::placeholder,
.textarea::placeholder {
  color: rgba(165, 174, 196, 0.7);
}

.input:focus-visible,
.select:focus-visible,
.textarea:focus-visible {
  outline: none;
  border-color: var(--color-primary);
  box-shadow: 0 0 0 1px var(--color-primary-soft);
}

.input[disabled],
.select[disabled],
.textarea[disabled] {
  opacity: 0.55;
  cursor: not-allowed;
}

.textarea {
  min-height: 120px;
  resize: vertical;
}

label {
  display: inline-block;
  margin-bottom: var(--space-2);
  font-size: var(--font-size-sm);
  color: var(--color-text);
}

.form-row {
  margin-bottom: var(--space-4);
}

.form-helper {
  margin-top: 4px;
  font-size: var(--font-size-xs);
  color: var(--color-text-muted);
}

.form-error {
  margin-top: 4px;
  font-size: var(--font-size-xs);
  color: var(--color-danger);
}

/* Card */

.card {
  background: linear-gradient(145deg, rgba(15, 23, 42, 0.96), rgba(15, 23, 42, 0.9));
  border-radius: var(--radius-xl);
  border: 1px solid rgba(148, 163, 184, 0.18);
  padding: var(--space-6);
  box-shadow: var(--shadow-soft);
  backdrop-filter: blur(18px);
}

.card--interactive {
  transition:
    transform var(--transition-base),
    box-shadow var(--transition-base),
    border-color var(--transition-base),
    background var(--transition-base);
}

.card--interactive:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-strong);
  border-color: rgba(247, 76, 47, 0.5);
  background: linear-gradient(145deg, rgba(15, 23, 42, 0.98), rgba(28, 37, 64, 0.96));
}

.card-header {
  margin-bottom: var(--space-4);
}

.card-title {
  font-size: var(--font-size-xl);
  margin-bottom: var(--space-1);
}

.card-subtitle {
  font-size: var(--font-size-sm);
  color: var(--color-text-muted);
}

/* =========================
 *  Accessibility & Motion
 * ========================= */

:focus-visible {
  outline: 2px solid var(--color-primary);
  outline-offset: 3px;
}

@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    scroll-behavior: auto !important;
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
  }
}