/* ===== Reset & Base ===== */
*, *::before, *::after { margin: 0; padding: 0; box-sizing: border-box; }
:root {
  --primary: #ff0000;
  --accent: #ff4500;
  --dark: #1e1b4b;
  --text: #1f2937;
  --muted: #6b7280;
  --border: #e5e7eb;
  --white: #ffffff;
}
html, body {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'PingFang TC', 'Microsoft JhengHei', Arial, sans-serif;
  color: var(--text);
  line-height: 1.5;
  background: #f0f2f5;
  overflow-x: hidden;
  width: 100%;
}

/* ===== Background ===== */
.bg-container {
  position: fixed; top: 0; left: 0; width: 100%; height: 100%; z-index: -2;
  background-image: url('../images/bg-main.webp');
  background-size: cover; background-position: center top; background-repeat: no-repeat;
}
.bg-overlay {
  position: fixed; top: 0; left: 0; width: 100%; height: 100%; z-index: -1;
  background: rgba(255,255,255,0.3);
}

/* ===== Layout ===== */
#app { width: 100%; overflow-x: hidden; }
.container {
  width: 100%;
  max-width: 800px;
  margin: 0 auto;
  padding: 0 16px;
}

/* ===== Header / Logo ===== */
.site-header {
  background: rgba(255,255,255,0.92);
  backdrop-filter: blur(10px);
  padding: 10px 0;
  position: sticky; top: 0; z-index: 200;
  box-shadow: 0 1px 6px rgba(0,0,0,0.08);
}
.header-content {
  display: flex;
  align-items: center;
  justify-content: flex-start;
}
.logo {
  display: flex;
  align-items: center;
  gap: 10px;
  text-decoration: none;
}
.logo-img {
  width: 44px;
  height: 44px;
  object-fit: contain;
  border-radius: 8px;
  flex-shrink: 0;
}
.logo-text {
  font-size: 18px;
  font-weight: 700;
  color: var(--dark);
  white-space: nowrap;
}

/* ===== Images — 全面自适应 ===== */
img {
  max-width: 100%;
  height: auto;
  display: block;
}
.hero-img,
.section-img,
.promo-img {
  width: 100%;
  max-width: 100%;
  height: auto;
  display: block;
  border-radius: 10px;
  overflow: hidden;
}
.hero-img { border-radius: 12px; box-shadow: 0 10px 20px rgba(0,0,0,0.15); }

/* ===== Hero ===== */
.hero-section { padding: 24px 0 16px; text-align: center; }
.hero-title {
  font-size: 32px; font-weight: 900;
  color: var(--accent) !important;
  margin-bottom: 10px;
  text-shadow: 0 2px 4px rgba(255,255,255,0.8);
  line-height: 1.2;
}
.hero-subtitle {
  font-size: 17px; color: var(--dark); font-weight: 600;
  background: rgba(255,255,255,0.75);
  padding: 5px 14px; border-radius: 50px;
  display: inline-block; margin-bottom: 16px;
}
.hero-highlights {
  display: flex; flex-direction: column; gap: 8px;
  max-width: 460px; margin: 0 auto 20px;
}
.highlight-item {
  display: flex; align-items: center; gap: 10px;
  font-size: 15px; font-weight: 800;
  color: var(--accent) !important;
  padding: 10px 15px;
  background: rgba(255,255,255,0.95);
  border-radius: 10px;
  box-shadow: 0 3px 8px rgba(0,0,0,0.06);
  border: 1px solid rgba(255,69,0,0.18);
  text-align: left;
}

/* ===== Sections ===== */
section { padding: 20px 0; }
.section-title {
  font-size: 22px; font-weight: 800;
  text-align: center; margin-bottom: 14px;
  color: var(--dark);
}
.section-desc {
  text-align: center; font-weight: 600;
  color: #374151; font-size: 15px; margin-top: 8px;
}

/* ===== Posters ===== */
.posters-section .container { padding: 0; }
.posters-section .section-title { padding: 0 16px; }
.posters-section .section-img {
  width: 100%;
  max-width: 100%;
  border-radius: 0;
  margin-bottom: 4px;
}

/* ===== Audience ===== */
.audience-list { display: flex; flex-direction: column; gap: 8px; margin-top: 10px; }
.audience-item {
  background: white; padding: 10px 14px;
  border-radius: 8px; font-weight: 600; font-size: 14px;
  box-shadow: 0 2px 5px rgba(0,0,0,0.05);
}

/* ===== Process Steps ===== */
.process-steps { margin-top: 10px; }
.step-card {
  display: flex; align-items: center; gap: 14px;
  background: white; padding: 12px 14px;
  border-radius: 10px; margin-bottom: 10px;
  box-shadow: 0 2px 5px rgba(0,0,0,0.05);
}
.step-num {
  background: var(--accent); color: white;
  width: 32px; height: 32px; border-radius: 50%;
  display: flex; align-items: center; justify-content: center;
  font-weight: 800; font-size: 15px; flex-shrink: 0;
}
.step-text { font-size: 14px; font-weight: 600; }

/* ===== Teacher ===== */
.teacher-card {
  background: white; padding: 20px;
  border-radius: 15px; box-shadow: 0 5px 15px rgba(0,0,0,0.06);
}
.teacher-info { display: flex; gap: 16px; align-items: center; }
.teacher-avatar {
  width: 72px; height: 72px; border-radius: 50%;
  object-fit: cover; flex-shrink: 0;
}
.teacher-text h3 { font-size: 18px; color: var(--dark); margin-bottom: 4px; }
.teacher-title { font-size: 13px; color: var(--accent); font-weight: 700; }
.teacher-bio { font-size: 13px; margin-top: 6px; line-height: 1.5; color: #4b5563; }

/* ===== Promo ===== */
.promo-section { padding: 10px 0; }
.promo-card {
  background: white; padding: 16px;
  border-radius: 15px; text-align: center;
  border: 2px solid var(--accent);
  box-shadow: 0 10px 30px rgba(255,69,0,0.1);
}
.price-box { padding: 10px 0; }
.old-price { text-decoration: line-through; color: #9ca3af; font-size: 15px; margin-right: 8px; }
.new-price { color: var(--primary); font-size: 26px; font-weight: 900; }

/* ===== Registration Section ===== */
.registration-section { padding: 20px 0 30px; }
.registration-card {
  background: rgba(255,255,255,0.95);
  border-radius: 16px; padding: 24px 20px;
  text-align: center;
  box-shadow: 0 8px 24px rgba(0,0,0,0.08);
}
.registration-label {
  font-size: 13px; color: var(--muted);
  text-transform: uppercase; letter-spacing: 1px;
  margin-bottom: 8px;
}
.registration-title {
  font-size: 18px; font-weight: 800;
  color: var(--dark); margin-bottom: 10px;
}
.registration-subtitle {
  font-size: 14px; color: #4b5563; margin-bottom: 18px;
}

/* ===== Buttons ===== */
.btn { display: inline-block; border: none; cursor: pointer; font-weight: 700; border-radius: 8px; }
.btn-primary { background: var(--primary); color: white; padding: 14px 20px; font-size: 16px; }
.btn-block { width: 100%; display: block; text-align: center; }

/* ===== Sticky Button ===== */
.sticky-register-button {
  position: fixed; bottom: 16px; left: 50%; transform: translateX(-50%);
  width: calc(100% - 32px); max-width: 450px;
  background: var(--primary); color: white;
  border: none; padding: 16px; border-radius: 50px;
  font-size: 19px; font-weight: 900;
  box-shadow: 0 8px 20px rgba(255,0,0,0.4);
  z-index: 999; cursor: pointer;
  display: flex; align-items: center; justify-content: center; gap: 10px;
  animation: pulse 2s infinite;
}
@keyframes pulse {
  0%   { transform: translateX(-50%) scale(1); }
  50%  { transform: translateX(-50%) scale(1.03); }
  100% { transform: translateX(-50%) scale(1); }
}
.bell-icon { font-size: 22px; animation: ring 1.5s infinite ease-in-out; }
@keyframes ring {
  0%   { transform: rotate(0); }
  10%  { transform: rotate(20deg); }
  20%  { transform: rotate(-20deg); }
  30%  { transform: rotate(15deg); }
  40%  { transform: rotate(-15deg); }
  50%  { transform: rotate(10deg); }
  60%  { transform: rotate(-10deg); }
  100% { transform: rotate(0); }
}

/* ===== Modal ===== */
.modal {
  display: none; position: fixed; z-index: 1000;
  left: 0; top: 0; width: 100%; height: 100%;
  background: rgba(0,0,0,0.75);
  overflow-y: auto;
}
.modal.active { display: flex; align-items: flex-start; justify-content: center; padding: 20px 0 100px; }
.modal-content {
  background: white; padding: 24px 20px;
  border-radius: 16px; width: calc(100% - 32px);
  max-width: 420px; position: relative;
}
.modal-close {
  position: absolute; top: 14px; right: 16px;
  background: none; border: none; font-size: 24px;
  cursor: pointer; color: #6b7280; line-height: 1;
}
.modal-content h2 {
  font-size: 20px; font-weight: 800; color: var(--dark);
  margin-bottom: 20px; text-align: center;
}

/* ===== Form ===== */
.registration-form { display: flex; flex-direction: column; gap: 14px; }
.form-group { display: flex; flex-direction: column; gap: 6px; }
.form-label { font-size: 14px; font-weight: 700; color: var(--dark); }
.required { color: var(--primary); }
.form-group input,
.form-group select {
  padding: 12px 14px;
  border: 1.5px solid var(--border);
  border-radius: 8px;
  width: 100%;
  font-size: 16px;
  color: var(--text);
  background: white;
  -webkit-appearance: none;
}
.form-group input:focus,
.form-group select:focus {
  outline: none;
  border-color: var(--accent);
  box-shadow: 0 0 0 3px rgba(255,69,0,0.12);
}
.phone-input-group { display: flex; gap: 8px; }
.phone-input-group select { width: 110px; flex-shrink: 0; }
.phone-input-group input { flex: 1; }
.form-hint {
  font-size: 12px; color: #ef4444; font-weight: 600;
  line-height: 1.5; margin-top: 2px;
}
.form-hint a { color: #ef4444; text-decoration: underline; }

/* ===== Date Options (radio style) ===== */
.date-options { display: flex; flex-direction: column; gap: 8px; }
.date-option {
  display: flex; align-items: center; gap: 10px;
  padding: 11px 14px;
  border: 1.5px solid var(--border);
  border-radius: 8px; cursor: pointer;
  font-size: 15px; font-weight: 600; color: var(--dark);
  background: white; transition: border-color 0.2s, background 0.2s;
}
.date-option input[type="radio"] { width: 18px; height: 18px; accent-color: var(--accent); flex-shrink: 0; }
.date-option:has(input:checked) {
  border-color: var(--accent);
  background: rgba(255,69,0,0.05);
}
.form-privacy { font-size: 12px; color: var(--muted); text-align: center; }

/* ===== Footer ===== */
.site-footer {
  background: var(--dark); color: white;
  padding: 30px 16px 110px;
}
.footer-brand {
  display: flex; align-items: center; gap: 12px;
  margin-bottom: 20px; justify-content: center;
}
.footer-logo {
  width: 44px; height: 44px; object-fit: contain;
  border-radius: 8px; flex-shrink: 0;
}
.footer-brand-text strong { font-size: 16px; display: block; }
.footer-brand-text p { font-size: 13px; color: #9ca3af; margin-top: 2px; }
.footer-links {
  display: flex; flex-wrap: wrap; justify-content: center;
  gap: 20px; margin-bottom: 20px;
}
.footer-col { min-width: 100px; }
.footer-col-title { font-size: 13px; font-weight: 700; color: white; margin-bottom: 8px; }
.footer-nav { display: flex; flex-direction: column; gap: 6px; }
.footer-nav a { color: #9ca3af; text-decoration: none; font-size: 13px; }
.footer-nav a:hover { color: white; }
.copyright { text-align: center; font-size: 12px; color: #6b7280; margin-top: 10px; }

/* ===== Mobile ===== */
@media (max-width: 480px) {
  .hero-title { font-size: 26px; }
  .section-title { font-size: 20px; }
  .new-price { font-size: 22px; }
  .sticky-register-button { font-size: 17px; padding: 14px; }
  .teacher-info { flex-direction: column; text-align: center; }
  .teacher-avatar { margin: 0 auto; }
  .footer-links { flex-direction: column; align-items: center; text-align: center; }
  .footer-nav { align-items: center; }
}