/* ===== Variables ===== */
:root {
  --bg: #0a0b0e;
  --bg-elevated: #12141a;
  --surface: #16181f;
  --border: rgba(255, 255, 255, 0.06);
  --text: #e8eaed;
  --text-muted: #9aa0a6;
  --accent: #5c7cfa;
  --accent-dim: rgba(92, 124, 250, 0.15);
  --accent-glow: rgba(92, 124, 250, 0.35);
  --success: #51cf66;
  --font-sans: 'DM Sans', -apple-system, BlinkMacSystemFont, sans-serif;
  --font-mono: 'JetBrains Mono', monospace;
  --radius: 12px;
  --radius-lg: 20px;
  --transition: 0.2s ease;
}

/* ===== Reset & Base ===== */
*, *::before, *::after { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  font-family: var(--font-sans);
  font-size: 16px;
  line-height: 1.6;
  color: var(--text);
  background: var(--bg);
  min-height: 100vh;
  overflow-x: hidden;
}

/* ===== Noise overlay ===== */
.noise {
  position: fixed;
  inset: 0;
  pointer-events: none;
  z-index: 9999;
  opacity: 0.03;
  background-image: url("data:image/svg+xml,%3Csvg viewBox='0 0 256 256' xmlns='http://www.w3.org/2000/svg'%3E%3Cfilter id='n'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.9' numOctaves='4' stitchTiles='stitch'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23n)'/%3E%3C/svg%3E");
}

/* ===== Header ===== */
.site-header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 100;
  padding: 1rem 1.5rem;
  background: rgba(10, 11, 14, 0.85);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border);
}
.header-inner {
  max-width: 1200px;
  margin: 0 auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1.5rem;
}
.logo {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  color: var(--text);
  text-decoration: none;
  font-weight: 600;
  font-size: 1.1rem;
}
.logo-icon {
  color: var(--accent);
  font-size: 1.25rem;
}
.nav {
  display: flex;
  gap: 2rem;
}
.nav a {
  color: var(--text-muted);
  text-decoration: none;
  font-size: 0.95rem;
  transition: color var(--transition);
}
.nav a:hover { color: var(--text); }

/* ===== Buttons ===== */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 0.6rem 1.25rem;
  font-family: var(--font-sans);
  font-size: 0.95rem;
  font-weight: 500;
  border-radius: var(--radius);
  text-decoration: none;
  transition: background var(--transition), color var(--transition), box-shadow var(--transition);
  border: none;
  cursor: pointer;
}
.btn-primary {
  background: var(--accent);
  color: #fff;
}
.btn-primary:hover {
  background: #6d8aff;
  box-shadow: 0 0 24px var(--accent-glow);
}
.btn-ghost {
  background: transparent;
  color: var(--text-muted);
  border: 1px solid var(--border);
}
.btn-ghost:hover {
  color: var(--text);
  border-color: rgba(255,255,255,0.12);
}
.btn-cta { padding: 0.5rem 1rem; font-size: 0.9rem; }
.btn-lg { padding: 0.85rem 1.75rem; font-size: 1rem; }

/* ===== Hero ===== */
.hero {
  position: relative;
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 6rem 1.5rem 4rem;
}
.hero-bg {
  position: absolute;
  inset: 0;
  overflow: hidden;
}
.hero-grid {
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(rgba(255,255,255,0.02) 1px, transparent 1px),
    linear-gradient(90deg, rgba(255,255,255,0.02) 1px, transparent 1px);
  background-size: 60px 60px;
  mask-image: radial-gradient(ellipse 80% 60% at 50% 40%, black, transparent 70%);
}
.hero-glow {
  position: absolute;
  border-radius: 50%;
  filter: blur(100px);
  opacity: 0.4;
}
.hero-glow-1 {
  width: 400px;
  height: 400px;
  background: var(--accent);
  top: 20%;
  left: 50%;
  transform: translate(-50%, -50%);
}
.hero-glow-2 {
  width: 300px;
  height: 300px;
  background: #3b5bdb;
  bottom: 10%;
  right: 20%;
}
.hero-inner {
  position: relative;
  max-width: 720px;
  text-align: center;
}
.hero-label {
  font-size: 0.85rem;
  font-weight: 500;
  color: var(--accent);
  text-transform: uppercase;
  letter-spacing: 0.12em;
  margin-bottom: 1rem;
}
.hero-title {
  font-size: clamp(2rem, 5vw, 3.25rem);
  font-weight: 700;
  line-height: 1.2;
  margin: 0 0 1.25rem;
  letter-spacing: -0.02em;
}
.hero-desc {
  font-size: 1.1rem;
  color: var(--text-muted);
  max-width: 560px;
  margin: 0 auto 2rem;
  line-height: 1.7;
}
.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 1rem;
  justify-content: center;
}

/* ===== Sections ===== */
.container {
  max-width: 1100px;
  margin: 0 auto;
  padding: 0 1.5rem;
}
.section-title {
  font-size: clamp(1.5rem, 3vw, 2rem);
  font-weight: 700;
  margin: 0 0 0.5rem;
  text-align: center;
}
.section-desc {
  color: var(--text-muted);
  text-align: center;
  margin: 0 0 3rem;
  max-width: 560px;
  margin-left: auto;
  margin-right: auto;
}
.pipeline-inline {
  text-align: center;
  font-size: 1rem;
  color: var(--text-muted);
  margin: 0 0 3rem;
  font-family: var(--font-mono);
  letter-spacing: 0.02em;
}
.flow-section .pipeline-inline { margin-bottom: 2rem; }

/* ===== Flow ===== */
.flow-section {
  padding: 5rem 0;
}
.flow-diagram {
  display: flex;
  align-items: stretch;
  justify-content: center;
  flex-wrap: wrap;
  gap: 0.75rem;
}
.flow-step {
  flex: 1 1 200px;
  max-width: 260px;
}
.flow-card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 1.5rem;
  height: 100%;
  transition: border-color var(--transition), box-shadow var(--transition);
}
.flow-card:hover {
  border-color: rgba(255,255,255,0.1);
  box-shadow: 0 8px 32px rgba(0,0,0,0.3);
}
.flow-card-highlight {
  border-color: var(--accent);
  background: linear-gradient(135deg, var(--surface) 0%, var(--accent-dim) 100%);
  box-shadow: 0 0 40px var(--accent-glow);
}
.flow-num {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 28px;
  height: 28px;
  background: var(--accent);
  color: #fff;
  font-size: 0.85rem;
  font-weight: 600;
  border-radius: 8px;
  margin-bottom: 1rem;
}
.flow-card h3 {
  font-size: 1.05rem;
  font-weight: 600;
  margin: 0 0 0.5rem;
}
.flow-card p {
  font-size: 0.9rem;
  color: var(--text-muted);
  margin: 0;
  line-height: 1.5;
}
.flow-arrow {
  display: flex;
  align-items: center;
  color: var(--text-muted);
  font-size: 1.25rem;
  flex-shrink: 0;
}
.flow-mobile {
  display: none;
  flex-direction: column;
  gap: 1rem;
  max-width: 400px;
  margin: 0 auto;
}
@media (max-width: 900px) {
  .flow-diagram { display: none; }
  .flow-mobile { display: flex; }
  .flow-section .section-desc,
  .flow-section .pipeline-inline { margin-bottom: 2rem; }
}

/* ===== Entry (Task submission) ===== */
.entry-section {
  padding: 4rem 0;
}
.entry-card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 3rem;
  text-align: center;
  position: relative;
  overflow: hidden;
}
.entry-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 3px;
  background: linear-gradient(90deg, transparent, var(--accent), transparent);
  opacity: 0.8;
}
.entry-badge {
  display: inline-block;
  font-size: 0.8rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  color: var(--accent);
  background: var(--accent-dim);
  padding: 0.35rem 0.85rem;
  border-radius: 999px;
  margin-bottom: 1.25rem;
}
.entry-title {
  font-size: clamp(1.35rem, 2.5vw, 1.75rem);
  font-weight: 700;
  margin: 0 0 1rem;
}
.entry-desc {
  color: var(--text-muted);
  max-width: 560px;
  margin: 0 auto 1.5rem;
  font-size: 1rem;
}
.entry-features {
  list-style: none;
  padding: 0;
  margin: 0 0 2rem;
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 1rem 1.5rem;
}
.entry-features li {
  font-size: 0.95rem;
  color: var(--text-muted);
  padding-left: 1.25rem;
  position: relative;
}
.entry-features li::before {
  content: '✓';
  position: absolute;
  left: 0;
  color: var(--success);
  font-weight: 600;
}
.entry-actions {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 0.75rem;
}
.entry-hint {
  font-size: 0.85rem;
  color: var(--text-muted);
}

/* ===== APIs ===== */
.apis-section {
  padding: 4rem 0;
}
.api-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 1.5rem;
}
.api-card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 1.75rem;
  transition: border-color var(--transition);
}
.api-card:hover { border-color: rgba(255,255,255,0.1); }
.api-icon {
  width: 44px;
  height: 44px;
  display: flex;
  align-items: center;
  justify-content: center;
  background: var(--accent-dim);
  color: var(--accent);
  font-family: var(--font-mono);
  font-weight: 600;
  font-size: 1.25rem;
  border-radius: 10px;
  margin-bottom: 1rem;
}
.api-card h3 {
  font-size: 1.1rem;
  font-weight: 600;
  margin: 0 0 0.5rem;
}
.api-card p {
  font-size: 0.9rem;
  color: var(--text-muted);
  margin: 0;
  line-height: 1.5;
}

/* ===== CTA block ===== */
.cta-section {
  padding: 4rem 0;
}
.cta-inner {
  background: linear-gradient(135deg, var(--surface) 0%, var(--accent-dim) 50%, var(--surface) 100%);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 3rem;
  text-align: center;
}
.cta-inner h2 {
  font-size: clamp(1.25rem, 2vw, 1.5rem);
  font-weight: 700;
  margin: 0 0 0.5rem;
}
.cta-inner p {
  color: var(--text-muted);
  margin: 0 0 1.5rem;
}
.cta-inner .btn { margin: 0; }

/* ===== Footer ===== */
.site-footer {
  padding: 2rem 1.5rem;
  border-top: 1px solid var(--border);
  text-align: center;
}
.site-footer p {
  margin: 0;
  font-size: 0.9rem;
  color: var(--text-muted);
}

/* ===== Task page & form ===== */
.task-page { padding-top: 5rem; padding-bottom: 4rem; min-height: 100vh; }
.task-hero { padding: 2rem 0 1.5rem; }
.task-title { font-size: clamp(1.5rem, 3vw, 2rem); font-weight: 700; margin: 0 0 0.5rem; text-align: center; }
.task-hero .pipeline-inline { margin-bottom: 0; }
.task-form-section { padding: 2rem 0; }
.container-narrow { max-width: 520px; margin-left: auto; margin-right: auto; }
.task-form {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 2rem;
}
.form-group { margin-bottom: 1.25rem; }
.form-label {
  display: block;
  font-size: 0.9rem;
  font-weight: 500;
  color: var(--text);
  margin-bottom: 0.4rem;
}
.task-form input,
.task-form select,
.task-form textarea {
  width: 100%;
  padding: 0.6rem 0.85rem;
  font-family: var(--font-sans);
  font-size: 1rem;
  color: var(--text);
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  transition: border-color var(--transition);
}
.task-form input::placeholder,
.task-form textarea::placeholder { color: var(--text-muted); opacity: 0.8; }
.task-form input:focus,
.task-form select:focus,
.task-form textarea:focus {
  outline: none;
  border-color: var(--accent);
}
.task-form input.input-error,
.task-form select.input-error { border-color: #e03131; }
.form-error {
  display: block;
  font-size: 0.8rem;
  color: #e03131;
  margin-top: 0.3rem;
  min-height: 1.2em;
}
.form-error.form-error-visible { margin-top: 0.35rem; }
.form-row { display: block; }
.form-row-2 { display: grid; grid-template-columns: 1fr 1fr; gap: 1rem; }
.form-actions { margin-top: 1.5rem; }

.date-range {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  flex-wrap: wrap;
}
.date-range-input {
  flex: 1 1 0;
  min-width: 0;
  cursor: pointer;
}
.date-range-input[readonly] { cursor: pointer; }
.date-range-sep {
  flex: 0 0 auto;
  font-size: 0.9rem;
  color: var(--text-muted);
  font-weight: 500;
}
.form-group-date-range .form-label { display: block; margin-bottom: 0.5rem; }
@media (max-width: 420px) {
  .date-range { flex-direction: column; align-items: stretch; gap: 0.5rem; }
  .date-range-sep { text-align: center; }
}

.completion-criteria {
  margin: 1.5rem 0;
  padding: 1.25rem;
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: var(--radius);
}
.completion-criteria-title {
  font-size: 1rem;
  font-weight: 600;
  margin: 0 0 1rem;
  color: var(--text);
}
.completion-criteria-placeholder {
  font-size: 0.9rem;
  color: var(--text-muted);
}
.completion-criteria-fields .form-group { margin-bottom: 1rem; }
.completion-criteria-fields .form-group:last-child { margin-bottom: 0; }

.form-success {
  background: var(--accent-dim);
  border: 1px solid var(--accent);
  color: var(--text);
  padding: 1.25rem 1.5rem;
  border-radius: var(--radius);
  font-size: 1rem;
  text-align: center;
  margin-top: 1rem;
}
@media (max-width: 540px) {
  .form-row-2 { grid-template-columns: 1fr; }
  .task-form { padding: 1.5rem; }
}

/* ===== Responsive ===== */
/* Prefer reduced motion */
@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after { animation-duration: 0.01ms !important; transition-duration: 0.01ms !important; }
}

@media (max-width: 640px) {
  .nav { display: none; }
  .hero { padding-top: 5rem; }
  .entry-card { padding: 2rem 1.5rem; }
}