/* ========================================
   榴星小将官网 - 全局样式
   设计风格：奇幻工业城 · 马卡龙色系
   ======================================== */

/* --- CSS Variables --- */
:root {
  --primary: #6C5CE7;       /* 薰衣草紫 */
  --primary-light: #A29BFE;   /* 浅紫 */
  --secondary: #74B9FF;      /* 天空蓝 */
  --accent: #FD79A8;         /* 樱花粉 */
  --accent-warm: #FDCB6E;    /* 暖黄 */
  --mint: #55EFC4;           /* 薄荷绿 */
  --coral: #FF7675;          /* 珊瑚红 */
  
  --bg: #FAFBFF;            /* 米白底 */
  --bg-alt: #F0F2FF;        /* 淡紫灰 */
  --card-bg: #FFFFFF;
  --text: #2D3436;          /* 深灰文字 */
  --text-light: #636E72;    /* 浅灰文字 */
  --border: #DFE6E9;
  
  --shadow: 0 4px 20px rgba(108, 92, 231, 0.1);
  --shadow-lg: 0 10px 40px rgba(108, 92, 231, 0.15);
  --radius: 16px;
  --radius-sm: 8px;
  
  --header-h: 70px;
}

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

html {
  scroll-behavior: smooth;
}

body {
  font-family: 'Noto Sans SC', -apple-system, BlinkMacSystemFont, sans-serif;
  color: var(--text);
  background: var(--bg);
  line-height: 1.7;
  overflow-x: hidden;
}

a {
  text-decoration: none;
  color: inherit;
  transition: color 0.2s;
}

ul { list-style: none; }

img {
  max-width: 100%;
  display: block;
}

h1, h2, h3, h4 {
  line-height: 1.3;
  font-weight: 600;
}

.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 24px;
}

/* --- Header --- */
.header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 1000;
  height: var(--header-h);
  background: rgba(250, 251, 255, 0.92);
  backdrop-filter: blur(16px);
  border-bottom: 1px solid rgba(108, 92, 231, 0.08);
  transition: all 0.3s;
}

.header.scrolled {
  box-shadow: var(--shadow);
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 100%;
}

.logo {
  display: flex;
  align-items: center;
  gap: 8px;
  font-weight: 700;
  font-size: 0.95rem;
  flex-shrink: 0;
}

.logo-img {
  height: 36px;
  width: auto;
  max-width: 220px;
  object-fit: contain;
}

.logo-icon {
  font-size: 1.4rem;
  flex-shrink: 0;
}

.logo-text {
  background: linear-gradient(135deg, var(--primary), var(--accent));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  white-space: nowrap;
}

.nav {
  display: flex;
  align-items: center;
  gap: 4px;
}

.nav-link {
  padding: 8px 12px;
  font-size: 0.92rem;
  font-weight: 500;
  color: var(--text-light);
  border-radius: var(--radius-sm);
  transition: all 0.2s;
  white-space: nowrap;
}

.nav-link:hover,
.nav-link.active {
  color: var(--primary);
  background: rgba(108, 92, 231, 0.08);
}

.nav-toggle {
  display: none;
  flex-direction: column;
  gap: 5px;
  background: none;
  border: none;
  cursor: pointer;
  padding: 8px;
}

.nav-toggle span {
  display: block;
  width: 24px;
  height: 2px;
  background: var(--text);
  border-radius: 2px;
  transition: all 0.3s;
}

/* --- Hero --- */
.hero {
  position: relative;
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: var(--header-h) 24px 60px;
  overflow: hidden;
  background: linear-gradient(135deg, #F0F2FF 0%, #FFF5F8 50%, #E8F4FF 100%);
}

.hero-bg {
  position: absolute;
  inset: 0;
  background:
    radial-gradient(ellipse at 20% 50%, rgba(108,92,231,0.12) 0%, transparent 50%),
    radial-gradient(ellipse at 80% 20%, rgba(253,121,168,0.1) 0%, transparent 40%),
    radial-gradient(ellipse at 60% 80%, rgba(116,185,255,0.1) 0%, transparent 40%);
  pointer-events: none;
}

.hero-content {
  position: relative;
  max-width: 700px;
  width: 100%;
  text-align: center;
}

.hero-subtitle {
  font-size: 1rem;
  color: var(--text-light);
  margin-bottom: 16px;
}

.hero-subtitle .highlight {
  color: var(--primary);
  font-weight: 600;
}

.hero-title {
  font-size: clamp(1.8rem, 5vw, 2.8rem);
  font-weight: 700;
  color: var(--text);
  margin-bottom: 20px;
  letter-spacing: -0.02em;
  line-height: 1.3;
}

.hero-title .highlight {
  background: linear-gradient(135deg, var(--primary), var(--accent));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.hero-desc {
  font-size: 1rem;
  color: var(--text-light);
  margin-bottom: 32px;
  line-height: 1.8;
}

.hero-btns {
  display: flex;
  gap: 12px;
  flex-wrap: wrap;
  justify-content: center;
}

.hero-tags {
  display: flex;
  gap: 10px;
  flex-wrap: wrap;
  justify-content: center;
  margin-top: 40px;
}

.tag {
  padding: 6px 14px;
  background: rgba(255,255,255,0.85);
  backdrop-filter: blur(8px);
  border: 1px solid rgba(108,92,231,0.15);
  border-radius: 50px;
  font-size: 0.85rem;
  font-weight: 500;
  color: var(--primary);
  box-shadow: 0 2px 8px rgba(108,92,231,0.1);
}

/* --- Buttons --- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 14px 32px;
  font-size: 1rem;
  font-weight: 600;
  border-radius: 50px;
  border: none;
  cursor: pointer;
  transition: all 0.3s;
  font-family: inherit;
}

.btn-primary {
  background: linear-gradient(135deg, var(--primary), #5B4BD5);
  color: #fff;
  box-shadow: 0 4px 16px rgba(108, 92, 231, 0.4);
}

.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 8px 24px rgba(108, 92, 231, 0.5);
}

.btn-outline {
  background: transparent;
  color: var(--primary);
  border: 2px solid var(--primary);
}

.btn-outline:hover {
  background: var(--primary);
  color: #fff;
  transform: translateY(-2px);
}

.btn-white {
  background: #fff;
  color: var(--primary);
  box-shadow: var(--shadow);
}

.btn-white:hover {
  transform: translateY(-2px);
  box-shadow: var(--shadow-lg);
}

/* --- Sections --- */
.section {
  padding: 100px 0;
}

.section-title {
  font-size: clamp(1.6rem, 3vw, 2.2rem);
  text-align: center;
  margin-bottom: 16px;
  color: var(--text);
}

.section-desc {
  text-align: center;
  color: var(--text-light);
  font-size: 1.05rem;
  margin-bottom: 60px;
}

.section-cta {
  text-align: center;
  margin-top: 48px;
}

/* --- Highlights --- */
.highlights {
  background: var(--card-bg);
}

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

.highlight-card {
  padding: 36px 28px;
  background: var(--bg);
  border-radius: var(--radius);
  text-align: center;
  transition: all 0.3s;
  border: 1px solid transparent;
}

.highlight-card:hover {
  transform: translateY(-6px);
  box-shadow: var(--shadow-lg);
  border-color: rgba(108,92,231,0.15);
}

.highlight-icon {
  font-size: 2.8rem;
  display: block;
  margin-bottom: 16px;
}

.highlight-card h3 {
  font-size: 1.15rem;
  margin-bottom: 10px;
}

.highlight-card p {
  font-size: 0.92rem;
  color: var(--text-light);
}

/* --- Courses Preview --- */
.courses-preview {
  background: linear-gradient(180deg, var(--bg) 0%, #F5F3FF 100%);
}

.courses-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 24px;
}

.course-card {
  background: var(--card-bg);
  border-radius: var(--radius);
  padding: 32px 28px;
  transition: all 0.3s;
  border: 1px solid var(--border);
}

.course-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-lg);
  border-color: var(--primary-light);
}

.course-img {
  font-size: 3rem;
  margin-bottom: 16px;
}

.course-card h3 {
  font-size: 1.2rem;
  margin-bottom: 10px;
}

.course-card p {
  font-size: 0.9rem;
  color: var(--text-light);
  margin-bottom: 16px;
  line-height: 1.7;
}

.course-more {
  font-size: 0.9rem;
  font-weight: 600;
  color: var(--primary);
}

/* --- About Preview --- */
.about-preview {
  background: var(--card-bg);
}

.about-preview-inner {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 60px;
  align-items: center;
}

.about-text h2 {
  font-size: 2rem;
  margin-bottom: 24px;
}

.about-text p {
  color: var(--text-light);
  margin-bottom: 16px;
  line-height: 1.9;
}

.about-stats {
  display: flex;
  gap: 40px;
  margin: 32px 0;
  padding: 24px 0;
  border-top: 1px solid var(--border);
  border-bottom: 1px solid var(--border);
}

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

.stat-num {
  font-size: 2rem;
  font-weight: 700;
  color: var(--primary);
}

.stat-label {
  font-size: 0.85rem;
  color: var(--text-light);
}

.about-img-placeholder {
  background: linear-gradient(135deg, var(--bg-alt), #E8F4FF);
  border-radius: var(--radius);
  aspect-ratio: 4/3;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.1rem;
  color: var(--text-light);
  border: 2px dashed var(--border);
}

/* --- CTA --- */
.cta {
  background: linear-gradient(135deg, var(--primary), #5B4BD5);
  text-align: center;
  padding: 80px 0;
}

.cta h2 {
  color: #fff;
  font-size: 2rem;
  margin-bottom: 12px;
}

.cta p {
  color: rgba(255,255,255,0.85);
  margin-bottom: 32px;
}

/* --- Footer --- */
.footer {
  background: var(--text);
  color: rgba(255,255,255,0.8);
  padding-top: 60px;
}

.footer-inner {
  display: grid;
  grid-template-columns: 1.5fr 2fr;
  gap: 60px;
  padding-bottom: 40px;
  border-bottom: 1px solid rgba(255,255,255,0.1);
}

.footer-brand .logo-icon {
  font-size: 1.5rem;
}

.footer-brand .logo-text {
  font-size: 1.2rem;
  background: linear-gradient(135deg, var(--primary-light), var(--accent));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.footer-brand p {
  margin-top: 12px;
  font-size: 0.9rem;
  color: rgba(255,255,255,0.6);
  max-width: 280px;
}

.footer-links {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 32px;
}

.footer-col h4 {
  color: #fff;
  font-size: 0.95rem;
  margin-bottom: 16px;
}

.footer-col a,
.footer-col p {
  display: block;
  font-size: 0.88rem;
  color: rgba(255,255,255,0.6);
  margin-bottom: 10px;
  transition: color 0.2s;
}

.footer-col a:hover {
  color: var(--primary-light);
}

.footer-bottom {
  padding: 20px 0;
  text-align: center;
  font-size: 0.82rem;
  color: rgba(255,255,255,0.4);
}

/* --- Page Header (共用) --- */
.page-header {
  background: linear-gradient(135deg, #F0F2FF 0%, #FFF5F8 100%);
  padding: 120px 0 60px;
  text-align: center;
}

.page-header h1 {
  font-size: clamp(1.8rem, 4vw, 2.6rem);
  margin-bottom: 12px;
}

.page-header p {
  color: var(--text-light);
  font-size: 1.05rem;
}

/* --- Responsive --- */
@media (max-width: 960px) {
  .about-preview-inner {
    grid-template-columns: 1fr;
    gap: 40px;
  }
  
  .footer-inner {
    grid-template-columns: 1fr;
    gap: 40px;
  }
  
  .footer-links {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (max-width: 768px) {
  .nav {
    position: fixed;
    top: var(--header-h);
    left: 0;
    right: 0;
    background: var(--card-bg);
    flex-direction: column;
    padding: 20px;
    gap: 4px;
    box-shadow: var(--shadow);
    transform: translateY(-100%);
    opacity: 0;
    pointer-events: none;
    transition: all 0.3s;
  }
  
  .nav.open {
    transform: translateY(0);
    opacity: 1;
    pointer-events: auto;
  }
  
  .nav-link {
    width: 100%;
    padding: 12px 16px;
  }
  
  .nav-toggle {
    display: flex;
  }
  
  .hero-content {
    padding: 40px 0;
  }
  
  .hero-tags {
    position: static;
    transform: none;
    margin-top: 40px;
    justify-content: flex-start;
  }
  
  .hero-btns {
    flex-direction: column;
  }
  
  .hero-btns .btn {
    width: 100%;
  }
  
  .section {
    padding: 60px 0;
  }
  
  .about-stats {
    flex-wrap: wrap;
    gap: 24px;
  }
  
  .footer-links {
    grid-template-columns: 1fr;
  }
}