/* ===== Design System ===== */
:root {
  --bg-primary: #e8eef7;
  --bg-card: #ffffff;
  --bg-card-hover: #f0f4fa;
  --bg-header: rgba(255, 255, 255, 0.85);
  --text-primary: #1a1a2e;
  --text-secondary: #4a4a6a;
  --text-muted: #8888a8;
  --accent: #3366cc;
  --accent-hover: #2952a3;
  --accent-light: #e6eeff;
  --correct: #22c55e;
  --correct-bg: #f0fdf4;
  --incorrect: #ef4444;
  --incorrect-bg: #fef2f2;
  --border: #d8dde8;
  --border-light: #e8ecf4;
  --shadow-sm: 0 1px 3px rgba(0,0,0,0.06);
  --shadow-md: 0 4px 12px rgba(0,0,0,0.08);
  --shadow-lg: 0 8px 32px rgba(0,0,0,0.12);
  --radius-sm: 8px;
  --radius-md: 12px;
  --radius-lg: 16px;
  --radius-xl: 24px;
  --font: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  --transition: 0.2s cubic-bezier(0.4, 0, 0.2, 1);
}

/* ===== Reset & Base ===== */
*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  scroll-behavior: smooth;
}

body {
  font-family: var(--font);
  background: var(--bg-primary);
  color: var(--text-primary);
  line-height: 1.6;
  min-height: 100vh;
  -webkit-font-smoothing: antialiased;
}

/* ===== View Management ===== */
.view {
  display: none;
}

.view.active {
  display: block;
}

/* ===== Header ===== */
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: var(--bg-header);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border-light);
}

.header-inner {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 24px;
  height: 64px;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.logo {
  font-size: 1.25rem;
  font-weight: 800;
  color: var(--text-primary);
  text-decoration: none;
  letter-spacing: -0.02em;
}

.header-nav {
  display: flex;
  gap: 24px;
}

.nav-link {
  font-size: 0.875rem;
  font-weight: 500;
  color: var(--text-secondary);
  text-decoration: none;
  padding: 6px 12px;
  border-radius: var(--radius-sm);
  transition: all var(--transition);
}

.nav-link:hover,
.nav-link.active {
  color: var(--accent);
  background: var(--accent-light);
}

/* ===== Beta Banner ===== */
.beta-banner {
  max-width: 1200px;
  margin: 24px auto 0;
  padding: 14px 24px;
  display: flex;
  align-items: center;
  gap: 12px;
  background: rgba(239, 68, 68, 0.07);
  border: 1px solid rgba(239, 68, 68, 0.22);
  border-radius: var(--radius-sm);
  font-size: 0.825rem;
  line-height: 1.5;
  color: #991b1b;
}

.beta-badge {
  flex-shrink: 0;
  padding: 3px 10px;
  font-size: 0.65rem;
  font-weight: 800;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: #92400e;
  background: rgba(234, 179, 8, 0.18);
  border: 1px solid rgba(234, 179, 8, 0.35);
  border-radius: 4px;
}

.beta-text {
  color: #78716c;
}

@media (max-width: 768px) {
  .beta-banner {
    margin: 16px 16px 0;
    flex-direction: column;
    align-items: flex-start;
    gap: 8px;
  }
}

/* ===== Tests Listing ===== */
.tests-main {
  max-width: 1200px;
  margin: 0 auto;
  padding: 40px 24px 80px;
}

.tests-hero {
  text-align: center;
  margin-bottom: 48px;
}

.tests-hero h1 {
  font-size: 2.5rem;
  font-weight: 800;
  letter-spacing: -0.03em;
  color: var(--text-primary);
  margin-bottom: 12px;
}

.tests-hero p {
  font-size: 1.125rem;
  color: var(--text-secondary);
  max-width: 500px;
  margin: 0 auto;
}

.tests-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(240px, 1fr));
  gap: 24px;
}

.test-card {
  background: var(--bg-card);
  border: 1px solid var(--border-light);
  border-radius: var(--radius-md);
  overflow: hidden;
  transition: all var(--transition);
  display: flex;
  flex-direction: column;
}

.test-card:hover {
  box-shadow: var(--shadow-lg);
  border-color: var(--border);
}

.test-card-image {
  width: 100%;
  aspect-ratio: 1;
  display: flex;
  align-items: center;
  justify-content: center;
  background: #f6f7fb;
  border-bottom: 1px solid var(--border-light);
  padding: 24px;
}

.test-card-image img {
  max-width: 80%;
  max-height: 80%;
  object-fit: contain;
}

.test-card-body {
  padding: 20px;
  display: flex;
  flex-direction: column;
  flex: 1;
}

.test-card-title {
  font-size: 1rem;
  font-weight: 700;
  color: var(--text-primary);
  letter-spacing: -0.01em;
  margin-bottom: 8px;
  line-height: 1.3;
}

.test-card-stats {
  display: flex;
  align-items: center;
  gap: 12px;
  font-size: 0.8rem;
  color: var(--text-muted);
  margin-bottom: 8px;
}

.test-card-stat {
  display: flex;
  align-items: center;
  gap: 4px;
}

.test-card-stat svg {
  width: 14px;
  height: 14px;
  flex-shrink: 0;
}

.test-card-desc {
  font-size: 0.8rem;
  color: var(--text-secondary);
  line-height: 1.45;
  margin-bottom: 20px;
  flex: 1;
}

.btn-start-test {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  width: fit-content;
  padding: 10px 24px;
  background: #1a6fb5;
  color: #fff;
  border: none;
  border-radius: 6px;
  font-family: var(--font);
  font-size: 0.75rem;
  font-weight: 700;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  cursor: pointer;
  transition: all var(--transition);
}

.btn-start-test:hover {
  background: #145a94;
  transform: translateY(-1px);
  box-shadow: var(--shadow-sm);
}

.btn-start-test svg {
  width: 14px;
  height: 14px;
}

/* ===== Landing Page ===== */
.landing-main {
  max-width: 800px;
  margin: 0 auto;
  padding: 60px 24px 80px;
}

.landing-card {
  background: var(--bg-card);
  border-radius: var(--radius-lg);
  padding: 48px;
  box-shadow: var(--shadow-md);
}

.landing-card h1 {
  font-size: 1.75rem;
  font-weight: 800;
  text-transform: uppercase;
  letter-spacing: 0.01em;
  color: var(--text-primary);
}

.landing-divider {
  border: none;
  height: 3px;
  background: var(--accent);
  margin: 20px 0 28px;
  border-radius: 2px;
}

.landing-card p {
  font-size: 0.95rem;
  color: var(--text-secondary);
  line-height: 1.7;
  margin-bottom: 16px;
}

.btn-begin {
  display: block;
  width: fit-content;
  margin: 32px auto 0;
  padding: 16px 48px;
  background: var(--text-primary);
  color: #fff;
  border: none;
  border-radius: var(--radius-sm);
  font-family: var(--font);
  font-size: 0.875rem;
  font-weight: 700;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  cursor: pointer;
  transition: all var(--transition);
}

.btn-begin:hover {
  background: var(--accent);
  transform: translateY(-1px);
  box-shadow: var(--shadow-md);
}

/* ===== Test Taking ===== */
.test-header {
  position: sticky;
  top: 0;
  z-index: 100;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 16px 24px;
  background: linear-gradient(135deg, #e0e8f8, #eaf0fb);
  border-bottom: 1px solid var(--border-light);
}

.test-home-link {
  position: absolute;
  right: 24px;
  top: 50%;
  transform: translateY(-50%);
  font-size: 0.875rem;
  font-weight: 500;
  color: var(--text-secondary);
  text-decoration: none;
  transition: color var(--transition);
}

.test-home-link:hover {
  color: var(--accent);
}

.test-timer {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-width: 90px;
  padding: 8px 20px;
  font-size: 1.25rem;
  font-weight: 700;
  font-variant-numeric: tabular-nums;
  color: var(--accent);
  background: var(--bg-card);
  border: 2px solid var(--accent);
  border-radius: 999px;
  letter-spacing: 0.02em;
}

.test-timer.warning {
  color: #e67700;
  border-color: #e67700;
  animation: pulse-warn 1s ease-in-out infinite;
}

.test-timer.danger {
  color: var(--incorrect);
  border-color: var(--incorrect);
  animation: pulse-danger 0.6s ease-in-out infinite;
}

@keyframes pulse-warn {
  0%, 100% { opacity: 1; }
  50% { opacity: 0.7; }
}

@keyframes pulse-danger {
  0%, 100% { opacity: 1; transform: scale(1); }
  50% { opacity: 0.8; transform: scale(1.03); }
}

.test-main {
  max-width: 900px;
  margin: 0 auto;
  padding: 32px 24px 48px;
}

/* Question cards */
.question-card {
  background: var(--bg-card);
  border: 1px solid var(--border-light);
  border-radius: var(--radius-md);
  padding: 32px;
  margin-bottom: 24px;
  box-shadow: var(--shadow-sm);
  transition: border-color var(--transition);
  display: flex;
  gap: 40px;
}

.question-card:hover {
  border-color: var(--border);
}

.question-left {
  flex: 1;
  min-width: 0;
}

.question-right {
  width: 200px;
  flex-shrink: 0;
}

.question-text {
  font-size: 0.95rem;
  color: var(--text-primary);
  margin-bottom: 16px;
  line-height: 1.6;
}

.question-prompt {
  font-size: 1.1rem;
  font-weight: 700;
  color: var(--text-primary);
  margin-bottom: 8px;
}

.question-image {
  max-width: 100%;
  margin: 16px auto;
  display: block;
  border-radius: var(--radius-sm);
}

.answer-label {
  font-size: 0.875rem;
  font-weight: 700;
  color: var(--text-primary);
  margin-bottom: 12px;
}

/* Radio options */
.radio-group {
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.radio-option {
  display: flex;
  align-items: center;
  gap: 10px;
  cursor: pointer;
  padding: 8px 12px;
  border-radius: var(--radius-sm);
  transition: background var(--transition);
  font-size: 0.9rem;
  color: var(--text-primary);
}

.radio-option:hover {
  background: var(--bg-card-hover);
}

.radio-option input[type="radio"] {
  width: 16px;
  height: 16px;
  accent-color: var(--accent);
  cursor: pointer;
  flex-shrink: 0;
}

/* Text input */
.answer-input {
  width: 100%;
  padding: 10px 14px;
  font-family: var(--font);
  font-size: 0.9rem;
  border: 1.5px solid var(--border);
  border-radius: var(--radius-sm);
  background: var(--bg-card);
  color: var(--text-primary);
  transition: border-color var(--transition);
  outline: none;
}

.answer-input:focus {
  border-color: var(--accent);
  box-shadow: 0 0 0 3px rgba(51, 102, 204, 0.12);
}

.answer-input::placeholder {
  color: var(--text-muted);
}

/* Hide number input spinners */
.answer-input::-webkit-outer-spin-button,
.answer-input::-webkit-inner-spin-button {
  -webkit-appearance: none;
  margin: 0;
}
.answer-input[type="number"] {
  -moz-appearance: textfield;
}

/* Submit */
.test-submit-area {
  padding: 32px 24px 80px;
  text-align: center;
}

.btn-submit {
  padding: 14px 64px;
  font-family: var(--font);
  font-size: 1rem;
  font-weight: 700;
  color: #fff;
  background: var(--accent);
  border: none;
  border-radius: var(--radius-sm);
  cursor: pointer;
  transition: all var(--transition);
  letter-spacing: 0.02em;
}

.btn-submit:hover {
  background: var(--accent-hover);
  transform: translateY(-1px);
  box-shadow: var(--shadow-md);
}

/* ===== Results ===== */
.results-main {
  max-width: 900px;
  margin: 0 auto;
  padding: 40px 24px 80px;
}

.results-card {
  background: var(--bg-card);
  border-radius: var(--radius-lg);
  padding: 48px;
  box-shadow: var(--shadow-md);
}

.results-card h1 {
  font-size: 2rem;
  font-weight: 800;
  text-align: center;
  margin-bottom: 32px;
  letter-spacing: -0.02em;
}

.results-summary {
  text-align: center;
  margin-bottom: 40px;
  padding: 32px;
  background: var(--bg-primary);
  border-radius: var(--radius-md);
}

.results-score {
  font-size: 3.5rem;
  font-weight: 800;
  color: var(--accent);
  line-height: 1;
}

.results-score-label {
  font-size: 0.875rem;
  color: var(--text-muted);
  margin-top: 8px;
  font-weight: 500;
}

.results-stats {
  display: flex;
  justify-content: center;
  gap: 48px;
  margin-top: 24px;
}

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

.results-stat-value {
  font-size: 1.5rem;
  font-weight: 700;
  color: var(--text-primary);
}

.results-stat-label {
  font-size: 0.8rem;
  color: var(--text-muted);
  margin-top: 4px;
}

/* Results breakdown */
.results-breakdown {
  margin-bottom: 32px;
}

.results-breakdown h2 {
  font-size: 1.25rem;
  font-weight: 700;
  margin-bottom: 20px;
  color: var(--text-primary);
}

.result-item {
  display: flex;
  align-items: flex-start;
  gap: 16px;
  padding: 16px 20px;
  margin-bottom: 8px;
  border-radius: var(--radius-sm);
  border-left: 4px solid transparent;
}

.result-item.correct {
  background: var(--correct-bg);
  border-left-color: var(--correct);
}

.result-item.incorrect {
  background: var(--incorrect-bg);
  border-left-color: var(--incorrect);
}

.result-item.unanswered {
  background: #f9fafb;
  border-left-color: var(--text-muted);
}

.result-icon {
  font-size: 1.25rem;
  flex-shrink: 0;
  width: 24px;
  text-align: center;
}

.result-content {
  flex: 1;
  min-width: 0;
}

.result-question-num {
  font-size: 0.75rem;
  font-weight: 600;
  color: var(--text-muted);
  text-transform: uppercase;
  letter-spacing: 0.04em;
  margin-bottom: 4px;
}

.result-question-text {
  font-size: 0.875rem;
  color: var(--text-primary);
  margin-bottom: 6px;
  line-height: 1.4;
}

.result-answers {
  font-size: 0.8rem;
  color: var(--text-secondary);
}

.result-answers span {
  font-weight: 600;
}

.result-your-answer {
  color: var(--incorrect);
}

.result-correct-answer {
  color: var(--correct);
}

.result-item.correct .result-your-answer {
  color: var(--correct);
}

/* Matrix images in results */
.result-matrix-images {
  margin-top: 8px;
}

.result-matrix-images img {
  max-width: 200px;
  border-radius: 4px;
}

/* ===== Footer ===== */
.site-footer {
  text-align: center;
  padding: 24px;
  font-size: 0.8rem;
  color: var(--text-muted);
  border-top: 1px solid var(--border-light);
  background: var(--bg-card);
}

/* ===== Responsive ===== */
@media (max-width: 768px) {
  .tests-hero h1 {
    font-size: 1.75rem;
  }

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

  .landing-card {
    padding: 28px;
  }

  .question-card {
    flex-direction: column;
    gap: 20px;
    padding: 20px;
  }

  .question-right {
    width: 100%;
  }

  .results-stats {
    gap: 24px;
  }
}

/* ===== Scroll to top for views ===== */
.view.active {
  animation: fadeIn 0.3s ease;
}

@keyframes fadeIn {
  from { opacity: 0; transform: translateY(8px); }
  to { opacity: 1; transform: translateY(0); }
}