/* ==========================================================================
   外婆云 (Waipoyun.lol) - 简洁银河科技风 CSS Design System
   ========================================================================== */

:root {
  --bg-dark: #070714;
  --bg-card: rgba(18, 16, 38, 0.72);
  --bg-card-hover: rgba(28, 25, 58, 0.85);
  --border-color: rgba(138, 92, 246, 0.22);
  --border-glow: rgba(0, 242, 254, 0.5);
  
  --primary-cyan: #00f2fe;
  --primary-blue: #4facfe;
  --primary-purple: #9d4edd;
  --primary-violet: #7000ff;
  --accent-pink: #ff007f;
  --accent-orange: #ff7e5f;
  
  --text-main: #f0f4fc;
  --text-muted: #94a3b8;
  --text-dim: #64748b;
  
  --gradient-main: linear-gradient(135deg, #00f2fe 0%, #7000ff 100%);
  --gradient-card: linear-gradient(145deg, rgba(255, 255, 255, 0.05) 0%, rgba(255, 255, 255, 0.01) 100%);
  --gradient-popular: linear-gradient(135deg, rgba(255, 126, 95, 0.15) 0%, rgba(112, 0, 255, 0.2) 100%);
  --gradient-glow: radial-gradient(circle at center, rgba(112, 0, 255, 0.3) 0%, transparent 70%);

  --font-sans: 'Inter', -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, "Noto Sans", sans-serif;
  --radius-sm: 8px;
  --radius-md: 16px;
  --radius-lg: 24px;
  --shadow-glow: 0 0 25px rgba(112, 0, 255, 0.25);
  --transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
  font-family: var(--font-sans);
  background-color: var(--bg-dark);
  color: var(--text-main);
  overflow-x: hidden;
}

body {
  position: relative;
  min-height: 100vh;
  line-height: 1.6;
}

/* Background Galaxy Canvas */
#galaxy-canvas {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  z-index: -1;
  pointer-events: none;
}

/* Galaxy Overlay Texture */
.galaxy-overlay {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: url('../images/galaxy-bg.png') center/cover no-repeat;
  opacity: 0.25;
  z-index: -2;
  pointer-events: none;
  filter: blur(2px);
}

/* Links & Buttons Reset */
a {
  color: inherit;
  text-decoration: none;
}

/* Container */
.container {
  max-width: 1240px;
  margin: 0 auto;
  padding: 0 24px;
}

/* Navigation Header */
.header {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  z-index: 1000;
  transition: var(--transition);
  padding: 18px 0;
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  background: rgba(7, 7, 20, 0.7);
  border-bottom: 1px solid rgba(255, 255, 255, 0.06);
}

.header.scrolled {
  padding: 12px 0;
  background: rgba(7, 7, 20, 0.92);
  box-shadow: 0 10px 30px rgba(0, 0, 0, 0.5);
  border-bottom-color: rgba(112, 0, 255, 0.3);
}

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

.logo {
  display: flex;
  align-items: center;
  gap: 12px;
  font-size: 1.4rem;
  font-weight: 800;
  letter-spacing: -0.5px;
  background: linear-gradient(135deg, #ffffff 30%, var(--primary-cyan) 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

.logo-icon {
  width: 38px;
  height: 38px;
  background: linear-gradient(135deg, var(--primary-cyan), var(--primary-violet));
  border-radius: 12px;
  display: flex;
  align-items: center;
  justify-content: center;
  box-shadow: 0 0 15px rgba(0, 242, 254, 0.4);
  color: #fff;
  font-size: 1.2rem;
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 32px;
  list-style: none;
}

.nav-links a {
  font-size: 0.95rem;
  font-weight: 500;
  color: var(--text-muted);
  transition: var(--transition);
  position: relative;
}

.nav-links a:hover,
.nav-links a.active {
  color: var(--text-main);
  text-shadow: 0 0 10px rgba(0, 242, 254, 0.5);
}

.nav-links a::after {
  content: '';
  position: absolute;
  bottom: -6px;
  left: 0;
  width: 0%;
  height: 2px;
  background: var(--gradient-main);
  transition: var(--transition);
  border-radius: 2px;
}

.nav-links a:hover::after,
.nav-links a.active::after {
  width: 100%;
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 12px 26px;
  border-radius: 50px;
  font-size: 0.95rem;
  font-weight: 600;
  cursor: pointer;
  transition: var(--transition);
  border: none;
  outline: none;
  white-space: nowrap;
}

.btn-primary {
  background: var(--gradient-main);
  color: #050510;
  font-weight: 700;
  box-shadow: 0 0 20px rgba(0, 242, 254, 0.35);
  position: relative;
  overflow: hidden;
}

.btn-primary::before {
  content: '';
  position: absolute;
  top: 0;
  left: -100%;
  width: 100%;
  height: 100%;
  background: linear-gradient(90deg, transparent, rgba(255, 255, 255, 0.4), transparent);
  transition: 0.5s;
}

.btn-primary:hover::before {
  left: 100%;
}

.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 0 30px rgba(0, 242, 254, 0.6);
}

.btn-secondary {
  background: rgba(255, 255, 255, 0.06);
  color: var(--text-main);
  border: 1px solid rgba(255, 255, 255, 0.15);
  backdrop-filter: blur(10px);
}

.btn-secondary:hover {
  background: rgba(255, 255, 255, 0.12);
  border-color: var(--primary-cyan);
  box-shadow: 0 0 15px rgba(0, 242, 254, 0.2);
  transform: translateY(-2px);
}

/* Mobile Nav Toggle */
.mobile-toggle {
  display: none;
  background: none;
  border: none;
  color: var(--text-main);
  font-size: 1.5rem;
  cursor: pointer;
}

/* Hero Section */
.hero {
  padding: 170px 0 100px;
  position: relative;
  text-align: center;
  overflow: hidden;
}

.hero-badge {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 8px 18px;
  background: rgba(112, 0, 255, 0.15);
  border: 1px solid rgba(138, 92, 246, 0.3);
  border-radius: 50px;
  font-size: 0.88rem;
  color: var(--primary-cyan);
  margin-bottom: 24px;
  backdrop-filter: blur(10px);
}

.hero-badge i {
  color: #ff007f;
}

.hero-title {
  font-size: 3.6rem;
  font-weight: 900;
  line-height: 1.15;
  margin-bottom: 24px;
  letter-spacing: -1px;
}

.hero-title span {
  background: linear-gradient(135deg, #00f2fe 0%, #9d4edd 50%, #ff007f 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

.hero-desc {
  font-size: 1.2rem;
  color: var(--text-muted);
  max-width: 780px;
  margin: 0 auto 40px;
  line-height: 1.7;
}

.hero-ctas {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 20px;
  margin-bottom: 60px;
  flex-wrap: wrap;
}

.hero-keywords {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 10px;
  max-width: 900px;
  margin: 0 auto;
}

.tag {
  font-size: 0.8rem;
  padding: 6px 14px;
  background: rgba(255, 255, 255, 0.04);
  border: 1px solid rgba(255, 255, 255, 0.08);
  border-radius: 30px;
  color: var(--text-muted);
  transition: var(--transition);
}

.tag:hover {
  border-color: var(--primary-cyan);
  color: var(--primary-cyan);
  background: rgba(0, 242, 254, 0.08);
}

/* Feature Cards Section */
.section {
  padding: 90px 0;
  position: relative;
}

.section-header {
  text-align: center;
  max-width: 700px;
  margin: 0 auto 60px;
}

.section-subtitle {
  font-size: 0.9rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 2px;
  color: var(--primary-cyan);
  margin-bottom: 12px;
}

.section-title {
  font-size: 2.5rem;
  font-weight: 800;
  margin-bottom: 16px;
}

.section-desc {
  font-size: 1.05rem;
  color: var(--text-muted);
}

.grid-3 {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
  gap: 30px;
}

.grid-4 {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 24px;
}

/* Sleek Galaxy Tech Cards */
.card {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  padding: 36px 28px;
  transition: var(--transition);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  position: relative;
  overflow: hidden;
}

.card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 2px;
  background: var(--gradient-main);
  opacity: 0;
  transition: var(--transition);
}

.card:hover {
  transform: translateY(-8px);
  border-color: var(--border-glow);
  box-shadow: 0 15px 35px rgba(0, 0, 0, 0.4), 0 0 20px rgba(0, 242, 254, 0.15);
  background: var(--bg-card-hover);
}

.card:hover::before {
  opacity: 1;
}

.card-icon {
  width: 56px;
  height: 56px;
  border-radius: 16px;
  background: rgba(112, 0, 255, 0.15);
  border: 1px solid rgba(138, 92, 246, 0.3);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.5rem;
  color: var(--primary-cyan);
  margin-bottom: 24px;
}

.card-title {
  font-size: 1.3rem;
  font-weight: 700;
  margin-bottom: 12px;
}

.card-desc {
  font-size: 0.95rem;
  color: var(--text-muted);
  line-height: 1.6;
}

/* Pricing Section - Exact to Figure 1 */
.pricing-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 30px;
  align-items: stretch;
}

.pricing-card {
  background: var(--bg-card);
  border: 1px dashed var(--border-color);
  border-radius: var(--radius-md);
  padding: 40px 30px;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  position: relative;
  transition: var(--transition);
  backdrop-filter: blur(16px);
}

.pricing-card.popular {
  border: 2px solid #ff7e5f;
  background: var(--gradient-popular);
  transform: scale(1.03);
  box-shadow: 0 0 35px rgba(255, 126, 95, 0.25);
}

.popular-badge {
  position: absolute;
  top: -16px;
  left: 50%;
  transform: translateX(-50%);
  background: linear-gradient(135deg, #ff7e5f, #eb4d4b);
  color: #fff;
  font-size: 0.85rem;
  font-weight: 700;
  padding: 6px 20px;
  border-radius: 20px;
  box-shadow: 0 4px 15px rgba(235, 77, 75, 0.4);
}

.plan-name {
  font-size: 1.8rem;
  font-weight: 800;
  text-align: center;
  margin-bottom: 20px;
  letter-spacing: -0.5px;
}

.plan-price {
  text-align: center;
  margin-bottom: 20px;
}

.price-currency {
  font-size: 1.5rem;
  font-weight: 700;
  color: #ff7e5f;
}

.price-amount {
  font-size: 3.2rem;
  font-weight: 900;
  color: #ff7e5f;
  line-height: 1;
}

.price-period {
  font-size: 1rem;
  color: var(--text-muted);
}

.plan-subtext {
  text-align: center;
  font-size: 0.95rem;
  color: var(--text-muted);
  margin-bottom: 30px;
  padding-bottom: 20px;
  border-bottom: 1px dashed rgba(255, 255, 255, 0.1);
}

.plan-features {
  list-style: none;
  margin-bottom: 36px;
  flex-grow: 1;
}

.plan-features li {
  display: flex;
  align-items: center;
  gap: 12px;
  font-size: 0.95rem;
  margin-bottom: 16px;
  color: var(--text-main);
}

.plan-features li i {
  color: #ff7e5f;
  font-size: 1rem;
}

.pricing-btn {
  width: 100%;
  padding: 14px 0;
  border-radius: var(--radius-sm);
  font-size: 1.05rem;
  font-weight: 700;
  border: 1px dashed rgba(255, 126, 95, 0.6);
  background: rgba(255, 255, 255, 0.05);
  color: var(--text-main);
  cursor: pointer;
  transition: var(--transition);
}

.pricing-card.popular .pricing-btn {
  background: linear-gradient(135deg, #ff7e5f, #eb4d4b);
  border: none;
  color: #fff;
  box-shadow: 0 6px 20px rgba(235, 77, 75, 0.4);
}

.pricing-btn:hover {
  background: linear-gradient(135deg, #ff7e5f, #eb4d4b);
  color: #fff;
  border-color: transparent;
  box-shadow: 0 8px 25px rgba(235, 77, 75, 0.5);
  transform: translateY(-2px);
}

/* Tutorial Tabs Section */
.tutorial-tabs {
  display: flex;
  justify-content: center;
  gap: 16px;
  margin-bottom: 40px;
  flex-wrap: wrap;
}

.tab-btn {
  padding: 12px 28px;
  background: rgba(255, 255, 255, 0.04);
  border: 1px solid rgba(255, 255, 255, 0.1);
  border-radius: 50px;
  color: var(--text-muted);
  font-size: 0.95rem;
  font-weight: 600;
  cursor: pointer;
  transition: var(--transition);
  display: flex;
  align-items: center;
  gap: 8px;
}

.tab-btn.active,
.tab-btn:hover {
  background: linear-gradient(135deg, rgba(0, 242, 254, 0.2), rgba(112, 0, 255, 0.2));
  border-color: var(--primary-cyan);
  color: var(--text-main);
  box-shadow: 0 0 15px rgba(0, 242, 254, 0.2);
}

.tab-content {
  display: none;
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  padding: 40px;
  backdrop-filter: blur(16px);
}

.tab-content.active {
  display: block;
  animation: fadeIn 0.4s ease-in-out;
}

@keyframes fadeIn {
  from { opacity: 0; transform: translateY(10px); }
  to { opacity: 1; transform: translateY(0); }
}

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

.step-item {
  background: rgba(255, 255, 255, 0.02);
  border: 1px solid rgba(255, 255, 255, 0.06);
  border-radius: var(--radius-sm);
  padding: 24px;
  position: relative;
}

.step-num {
  width: 32px;
  height: 32px;
  background: var(--gradient-main);
  color: #050510;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 800;
  margin-bottom: 16px;
}

.step-title {
  font-size: 1.1rem;
  font-weight: 700;
  margin-bottom: 8px;
}

.step-desc {
  font-size: 0.9rem;
  color: var(--text-muted);
}

/* Articles Section */
.article-card {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  padding: 30px;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  transition: var(--transition);
  backdrop-filter: blur(16px);
}

.article-card:hover {
  transform: translateY(-6px);
  border-color: var(--primary-cyan);
  box-shadow: 0 12px 30px rgba(0, 0, 0, 0.4), 0 0 20px rgba(0, 242, 254, 0.2);
}

.article-meta {
  display: flex;
  align-items: center;
  gap: 12px;
  font-size: 0.85rem;
  color: var(--primary-cyan);
  margin-bottom: 12px;
}

.article-title {
  font-size: 1.25rem;
  font-weight: 700;
  margin-bottom: 14px;
  line-height: 1.4;
}

.article-snippet {
  font-size: 0.92rem;
  color: var(--text-muted);
  margin-bottom: 20px;
  line-height: 1.6;
}

.article-link {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  font-size: 0.9rem;
  font-weight: 700;
  color: var(--primary-cyan);
  transition: var(--transition);
}

.article-link:hover {
  gap: 10px;
  color: #fff;
}

/* FAQ Accordion */
.faq-list {
  max-width: 900px;
  margin: 0 auto;
  display: flex;
  flex-direction: column;
  gap: 16px;
}

.faq-item {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  overflow: hidden;
  transition: var(--transition);
}

.faq-question {
  padding: 24px 28px;
  font-size: 1.1rem;
  font-weight: 700;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: space-between;
  user-select: none;
}

.faq-question i {
  color: var(--primary-cyan);
  transition: var(--transition);
}

.faq-answer {
  max-height: 0;
  overflow: hidden;
  transition: max-height 0.3s ease-out, padding 0.3s ease;
  padding: 0 28px;
  color: var(--text-muted);
  font-size: 0.98rem;
  line-height: 1.7;
  border-top: 1px solid transparent;
}

.faq-item.active {
  border-color: var(--primary-cyan);
  background: var(--bg-card-hover);
}

.faq-item.active .faq-question i {
  transform: rotate(180deg);
}

.faq-item.active .faq-answer {
  max-height: 500px;
  padding: 0 28px 24px;
  border-top-color: rgba(255, 255, 255, 0.06);
}

/* Testimonials Section */
.testimonial-card {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  padding: 30px;
  position: relative;
}

.user-info {
  display: flex;
  align-items: center;
  gap: 14px;
  margin-bottom: 16px;
}

.avatar {
  width: 46px;
  height: 46px;
  border-radius: 50%;
  background: var(--gradient-main);
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 800;
  color: #050510;
  font-size: 1.1rem;
}

.user-name {
  font-weight: 700;
  font-size: 1.05rem;
}

.user-role {
  font-size: 0.82rem;
  color: var(--text-muted);
}

.stars {
  color: #ffb703;
  margin-bottom: 14px;
  font-size: 0.9rem;
}

.comment {
  font-size: 0.95rem;
  color: var(--text-muted);
  line-height: 1.6;
}

/* Footer Section */
.footer {
  background: rgba(5, 5, 14, 0.95);
  border-top: 1px solid rgba(255, 255, 255, 0.08);
  padding: 80px 0 40px;
  margin-top: 60px;
}

.footer-grid {
  display: grid;
  grid-template-columns: 2fr repeat(3, 1fr);
  gap: 40px;
  margin-bottom: 60px;
}

.footer-brand p {
  color: var(--text-muted);
  font-size: 0.92rem;
  margin-top: 16px;
  max-width: 340px;
}

.footer-title {
  font-size: 1.05rem;
  font-weight: 700;
  margin-bottom: 20px;
  color: var(--text-main);
}

.footer-links {
  list-style: none;
}

.footer-links li {
  margin-bottom: 12px;
}

.footer-links a {
  color: var(--text-muted);
  font-size: 0.9rem;
  transition: var(--transition);
}

.footer-links a:hover {
  color: var(--primary-cyan);
  padding-left: 4px;
}

.footer-bottom {
  text-align: center;
  padding-top: 30px;
  border-top: 1px solid rgba(255, 255, 255, 0.05);
  color: var(--text-dim);
  font-size: 0.88rem;
}

/* Floating Action Button */
.float-cta {
  position: fixed;
  bottom: 30px;
  right: 30px;
  z-index: 999;
  box-shadow: 0 10px 30px rgba(0, 242, 254, 0.5);
  animation: pulse 2s infinite;
}

@keyframes pulse {
  0% { transform: scale(1); box-shadow: 0 0 0 0 rgba(0, 242, 254, 0.7); }
  70% { transform: scale(1.05); box-shadow: 0 0 0 15px rgba(0, 242, 254, 0); }
  100% { transform: scale(1); box-shadow: 0 0 0 0 rgba(0, 242, 254, 0); }
}

/* Article Detail Layout */
.article-detail {
  padding: 160px 0 100px;
  max-width: 860px;
  margin: 0 auto;
}

.article-header-box {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  padding: 40px;
  margin-bottom: 40px;
  backdrop-filter: blur(16px);
}

.article-content {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  padding: 48px;
  line-height: 1.85;
  font-size: 1.05rem;
  color: #e2e8f0;
  backdrop-filter: blur(16px);
}

.article-content h1, 
.article-content h2, 
.article-content h3 {
  color: #fff;
  margin: 36px 0 18px;
  line-height: 1.3;
}

.article-content h2 {
  font-size: 1.7rem;
  border-bottom: 1px solid rgba(255, 255, 255, 0.1);
  padding-bottom: 10px;
  color: var(--primary-cyan);
}

.article-content h3 {
  font-size: 1.3rem;
  color: var(--primary-purple);
}

.article-content p {
  margin-bottom: 20px;
}

.article-content ul, .article-content ol {
  margin: 0 0 24px 24px;
}

.article-content li {
  margin-bottom: 10px;
}

.article-content code {
  background: rgba(0, 242, 254, 0.1);
  color: var(--primary-cyan);
  padding: 3px 8px;
  border-radius: 4px;
  font-family: monospace;
}

.article-cta-box {
  margin: 40px 0;
  padding: 30px;
  background: linear-gradient(135deg, rgba(0, 242, 254, 0.1), rgba(112, 0, 255, 0.15));
  border: 1px solid var(--primary-cyan);
  border-radius: var(--radius-md);
  text-align: center;
}

.article-cta-box h3 {
  margin-top: 0;
  color: #fff;
}

/* Responsive Rules */
@media (max-width: 992px) {
  .pricing-grid {
    grid-template-columns: 1fr;
    max-width: 480px;
    margin: 0 auto;
  }
  
  .pricing-card.popular {
    transform: scale(1);
  }
  
  .footer-grid {
    grid-template-columns: 1fr 1fr;
  }
}

@media (max-width: 768px) {
  .hero-title {
    font-size: 2.4rem;
  }
  
  .nav-links {
    position: fixed;
    top: 70px;
    left: -100%;
    width: 100%;
    height: calc(100vh - 70px);
    background: rgba(7, 7, 20, 0.98);
    flex-direction: column;
    justify-content: center;
    gap: 30px;
    transition: var(--transition);
  }
  
  .nav-links.active {
    left: 0;
  }
  
  .mobile-toggle {
    display: block;
  }
  
  .footer-grid {
    grid-template-columns: 1fr;
  }

  .article-content {
    padding: 24px;
  }
}