/* ===== 全局重置 & 基础样式 ===== */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

:root {
    --primary: #6C63FF;
    --primary-dark: #5A52D5;
    --primary-light: #8B85FF;
    --secondary: #FF6584;
    --accent: #00D2FF;
    --bg-dark: #0a0a1a;
    --bg-card: #12122a;
    --bg-card-hover: #1a1a3a;
    --text-primary: #ffffff;
    --text-secondary: #b0b0d0;
    --text-muted: #6b6b8d;
    --border-color: #2a2a4a;
    --gradient-1: linear-gradient(135deg, #6C63FF, #FF6584);
    --gradient-2: linear-gradient(135deg, #6C63FF, #00D2FF);
    --gradient-3: linear-gradient(135deg, #FF6584, #FFB347);
    --shadow: 0 8px 32px rgba(108, 99, 255, 0.15);
    --shadow-lg: 0 16px 48px rgba(108, 99, 255, 0.25);
    --radius: 16px;
    --radius-sm: 8px;
    --radius-lg: 24px;
}

html {
    scroll-behavior: smooth;
}

body {
    font-family: 'Noto Sans SC', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
    background: var(--bg-dark);
    color: var(--text-primary);
    line-height: 1.6;
    overflow-x: hidden;
}

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

/* ===== 渐变文字 ===== */
.gradient-text {
    background: var(--gradient-1);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

/* ===== 导航栏 ===== */
.navbar {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 1000;
    background: rgba(10, 10, 26, 0.8);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    border-bottom: 1px solid rgba(42, 42, 74, 0.5);
    transition: all 0.3s ease;
}

.navbar .container {
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 72px;
}

.logo {
    display: flex;
    align-items: center;
    gap: 8px;
}

.logo-icon {
    font-size: 28px;
    animation: float 3s ease-in-out infinite;
}

.logo-text {
    font-size: 24px;
    font-weight: 900;
    background: var(--gradient-2);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.logo-sub {
    font-size: 12px;
    color: var(--text-secondary);
    margin-left: 4px;
    padding: 2px 8px;
    background: rgba(108, 99, 255, 0.15);
    border-radius: 20px;
    font-weight: 500;
}

.nav-links {
    display: flex;
    align-items: center;
    gap: 32px;
}

.nav-links a {
    color: var(--text-secondary);
    text-decoration: none;
    font-size: 15px;
    font-weight: 500;
    transition: color 0.3s ease;
    position: relative;
}

.nav-links a::after {
    content: '';
    position: absolute;
    bottom: -4px;
    left: 0;
    width: 0;
    height: 2px;
    background: var(--gradient-1);
    transition: width 0.3s ease;
}

.nav-links a:hover {
    color: var(--text-primary);
}

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

.btn-nav {
    padding: 10px 24px !important;
    background: var(--gradient-1);
    border-radius: 50px !important;
    color: white !important;
    font-weight: 600 !important;
    transition: transform 0.3s ease, box-shadow 0.3s ease !important;
}

.btn-nav::after {
    display: none !important;
}

.btn-nav:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 24px rgba(108, 99, 255, 0.4);
}

/* 汉堡菜单 */
.menu-toggle {
    display: none;
    flex-direction: column;
    gap: 5px;
    cursor: pointer;
    padding: 4px;
}

.menu-toggle span {
    width: 28px;
    height: 3px;
    background: var(--text-primary);
    border-radius: 2px;
    transition: all 0.3s ease;
}

/* ===== Hero 区域 ===== */
.hero {
    min-height: 100vh;
    display: flex;
    align-items: center;
    position: relative;
    overflow: hidden;
    padding-top: 72px;
}

.hero::before {
    content: '';
    position: absolute;
    top: -50%;
    left: -50%;
    width: 200%;
    height: 200%;
    background: radial-gradient(circle at 30% 50%, rgba(108, 99, 255, 0.08) 0%, transparent 50%),
                radial-gradient(circle at 70% 50%, rgba(255, 101, 132, 0.06) 0%, transparent 50%);
    animation: gradientShift 15s ease-in-out infinite;
}

.hero .container {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 60px;
    align-items: center;
    position: relative;
    z-index: 1;
}

.hero-badge {
    display: inline-block;
    padding: 8px 20px;
    background: rgba(108, 99, 255, 0.15);
    border: 1px solid rgba(108, 99, 255, 0.3);
    border-radius: 50px;
    font-size: 14px;
    color: var(--primary-light);
    margin-bottom: 24px;
    animation: fadeInUp 0.6s ease;
}

.hero-title {
    font-size: 64px;
    font-weight: 900;
    line-height: 1.1;
    margin-bottom: 24px;
    animation: fadeInUp 0.6s ease 0.1s both;
}

.hero-desc {
    font-size: 18px;
    color: var(--text-secondary);
    margin-bottom: 36px;
    line-height: 1.8;
    animation: fadeInUp 0.6s ease 0.2s both;
}

.hero-actions {
    display: flex;
    gap: 16px;
    margin-bottom: 48px;
    animation: fadeInUp 0.6s ease 0.3s both;
}

.btn-primary {
    display: inline-block;
    padding: 16px 36px;
    background: var(--gradient-1);
    color: white;
    text-decoration: none;
    border-radius: 50px;
    font-weight: 600;
    font-size: 16px;
    border: none;
    cursor: pointer;
    transition: all 0.3s ease;
    position: relative;
    overflow: hidden;
}

.btn-primary::before {
    content: '';
    position: absolute;
    top: 0;
    left: -100%;
    width: 100%;
    height: 100%;
    background: linear-gradient(90deg, transparent, rgba(255,255,255,0.2), transparent);
    transition: left 0.5s ease;
}

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

.btn-primary:hover {
    transform: translateY(-3px);
    box-shadow: 0 12px 32px rgba(108, 99, 255, 0.4);
}

.btn-secondary {
    display: inline-block;
    padding: 16px 36px;
    background: transparent;
    color: var(--text-primary);
    text-decoration: none;
    border-radius: 50px;
    font-weight: 600;
    font-size: 16px;
    border: 2px solid var(--border-color);
    cursor: pointer;
    transition: all 0.3s ease;
}

.btn-secondary:hover {
    border-color: var(--primary);
    background: rgba(108, 99, 255, 0.1);
    transform: translateY(-3px);
}

.btn-full {
    width: 100%;
    text-align: center;
}

.hero-stats {
    display: flex;
    gap: 40px;
    animation: fadeInUp 0.6s ease 0.4s both;
}

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

.stat-number {
    font-size: 28px;
    font-weight: 900;
    background: var(--gradient-2);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.stat-label {
    font-size: 14px;
    color: var(--text-muted);
    margin-top: 4px;
}

/* Hero 视觉元素 */
.hero-visual {
    position: relative;
    height: 500px;
    display: flex;
    align-items: center;
    justify-content: center;
}

.floating-envelope {
    font-size: 120px;
    animation: float 4s ease-in-out infinite;
    filter: drop-shadow(0 20px 40px rgba(108, 99, 255, 0.3));
}

.floating-envelope.small {
    font-size: 60px;
    position: absolute;
    top: 20%;
    right: 10%;
    animation: float 5s ease-in-out infinite 1s;
}

.floating-envelope.tiny {
    font-size: 40px;
    position: absolute;
    bottom: 20%;
    left: 10%;
    animation: float 3.5s ease-in-out infinite 0.5s;
}

/* ===== 注册表单 ===== */
.register {
    padding: 100px 0;
    position: relative;
}

.register::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 1px;
    background: linear-gradient(90deg, transparent, var(--border-color), transparent);
}

.section-header {
    text-align: center;
    margin-bottom: 60px;
}

.section-header h2 {
    font-size: 42px;
    font-weight: 800;
    margin-bottom: 16px;
}

.section-header p {
    font-size: 18px;
    color: var(--text-secondary);
}

.register-card {
    max-width: 640px;
    margin: 0 auto;
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-lg);
    padding: 48px;
    box-shadow: var(--shadow);
    transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.register-card:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-lg);
}

.form-row {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 20px;
    margin-bottom: 20px;
}

.form-group {
    margin-bottom: 20px;
}

.form-group label {
    display: block;
    font-size: 14px;
    font-weight: 600;
    color: var(--text-secondary);
    margin-bottom: 8px;
}

.form-group input,
.form-group select {
    width: 100%;
    padding: 14px 16px;
    background: rgba(255, 255, 255, 0.05);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-sm);
    color: var(--text-primary);
    font-size: 15px;
    font-family: inherit;
    transition: all 0.3s ease;
    outline: none;
}

.form-group input:focus,
.form-group select:focus {
    border-color: var(--primary);
    box-shadow: 0 0 0 3px rgba(108, 99, 255, 0.15);
    background: rgba(108, 99, 255, 0.05);
}

.form-group select {
    cursor: pointer;
    appearance: none;
    background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='12' height='12' viewBox='0 0 12 12'%3E%3Cpath fill='%23b0b0d0' d='M6 8L1 3h10z'/%3E%3C/svg%3E");
    background-repeat: no-repeat;
    background-position: right 16px center;
}

.form-group select option {
    background: var(--bg-card);
    color: var(--text-primary);
}

.input-hint {
    display: block;
    font-size: 12px;
    color: var(--text-muted);
    margin-top: 6px;
}

.checkbox-group {
    margin-bottom: 24px;
}

.checkbox-label {
    display: flex;
    align-items: center;
    gap: 10px;
    cursor: pointer;
    font-size: 14px;
    color: var(--text-secondary);
}

.checkbox-label input[type="checkbox"] {
    width: 18px;
    height: 18px;
    accent-color: var(--primary);
    cursor: pointer;
}

.checkbox-label a {
    color: var(--primary-light);
    text-decoration: none;
}

.checkbox-label a:hover {
    text-decoration: underline;
}

.register-note {
    text-align: center;
    margin-top: 24px;
    padding-top: 24px;
    border-top: 1px solid var(--border-color);
}

.register-note p {
    color: var(--text-secondary);
    font-size: 14px;
}

.register-note a {
    color: var(--primary-light);
    text-decoration: none;
    font-weight: 600;
}

.register-note a:hover {
    text-decoration: underline;
}

/* ===== 功能特点 ===== */
.features {
    padding: 100px 0;
    background: var(--bg-card);
}

.features-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 24px;
}

.feature-card {
    background: var(--bg-dark);
    border: 1px solid var(--border-color);
    border-radius: var(--radius);
    padding: 36px;
    transition: all 0.3s ease;
    cursor: default;
}

.feature-card:hover {
    transform: translateY(-8px);
    border-color: var(--primary);
    box-shadow: 0 12px 40px rgba(108, 99, 255, 0.15);
}

.feature-icon {
    font-size: 40px;
    margin-bottom: 20px;
}

.feature-card h3 {
    font-size: 20px;
    font-weight: 700;
    margin-bottom: 12px;
}

.feature-card p {
    color: var(--text-secondary);
    font-size: 15px;
    line-height: 1.7;
}

/* ===== 价格方案 ===== */
.pricing {
    padding: 100px 0;
}

.pricing-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 24px;
    align-items: start;
}

.pricing-card {
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-lg);
    padding: 40px 32px;
    position: relative;
    transition: all 0.3s ease;
}

.pricing-card:hover {
    transform: translateY(-8px);
    box-shadow: var(--shadow);
}

.pricing-card.popular {
    border-color: var(--primary);
    box-shadow: 0 0 40px rgba(108, 99, 255, 0.15);
    transform: scale(1.05);
}

.pricing-card.popular:hover {
    transform: scale(1.05) translateY(-8px);
}

.popular-badge {
    position: absolute;
    top: -12px;
    left: 50%;
    transform: translateX(-50%);
    padding: 6px 24px;
    background: var(--gradient-1);
    border-radius: 50px;
    font-size: 13px;
    font-weight: 600;
    white-space: nowrap;
}

.pricing-header {
    text-align: center;
    margin-bottom: 32px;
    padding-bottom: 24px;
    border-bottom: 1px solid var(--border-color);
}

.pricing-header h3 {
    font-size: 22px;
    font-weight: 700;
    margin-bottom: 16px;
}

.price {
    display: flex;
    align-items: baseline;
    justify-content: center;
    gap: 4px;
}

.price .amount {
    font-size: 48px;
    font-weight: 900;
    background: var(--gradient-2);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.price .period {
    font-size: 16px;
    color: var(--text-muted);
}

.pricing-features {
    list-style: none;
    margin-bottom: 32px;
}

.pricing-features li {
    padding: 10px 0;
    color: var(--text-secondary);
    font-size: 15px;
    border-bottom: 1px solid rgba(42, 42, 74, 0.5);
}

.pricing-features li:last-child {
    border-bottom: none;
}

/* ===== 常见问题 ===== */
.faq {
    padding: 100px 0;
    background: var(--bg-card);
}

.faq-list {
    max-width: 800px;
    margin: 0 auto;
}

.faq-item {
    background: var(--bg-dark);
    border: 1px solid var(--border-color);
    border-radius: var(--radius);
    margin-bottom: 16px;
    overflow: hidden;
    cursor: pointer;
    transition: all 0.3s ease;
}

.faq-item:hover {
    border-color: var(--primary);
}

.faq-question {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 20px 24px;
    font-size: 16px;
    font-weight: 600;
}

.faq-arrow {
    font-size: 12px;
    transition: transform 0.3s ease;
    color: var(--text-muted);
}

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

.faq-answer {
    max-height: 0;
    overflow: hidden;
    transition: max-height 0.3s ease, padding 0.3s ease;
}

.faq-item.active .faq-answer {
    max-height: 300px;
    padding: 0 24px 20px;
}

.faq-answer p {
    color: var(--text-secondary);
    font-size: 15px;
    line-height: 1.8;
}

/* ===== 页脚 ===== */
.footer {
    padding: 80px 0 0;
    border-top: 1px solid var(--border-color);
}

.footer-grid {
    display: grid;
    grid-template-columns: 2fr 1fr 1fr 1fr 1.5fr;
    gap: 40px;
    margin-bottom: 60px;
}

.footer-brand .logo {
    margin-bottom: 16px;
}

.footer-brand p {
    color: var(--text-secondary);
    font-size: 15px;
    margin-bottom: 24px;
}

.social-links {
    display: flex;
    gap: 12px;
}

.social-links a {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 40px;
    height: 40px;
    background: rgba(255, 255, 255, 0.05);
    border-radius: 50%;
    font-size: 18px;
    text-decoration: none;
    transition: all 0.3s ease;
}

.social-links a:hover {
    background: var(--primary);
    transform: translateY(-3px);
}

.footer-links h4,
.footer-contact h4 {
    font-size: 16px;
    font-weight: 700;
    margin-bottom: 20px;
}

.footer-links a {
    display: block;
    color: var(--text-secondary);
    text-decoration: none;
    font-size: 14px;
    margin-bottom: 12px;
    transition: color 0.3s ease;
}

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

.footer-contact p {
    color: var(--text-secondary);
    font-size: 14px;
    margin-bottom: 12px;
}

.footer-bottom {
    padding: 24px 0;
    border-top: 1px solid var(--border-color);
    text-align: center;
}

.footer-bottom p {
    color: var(--text-muted);
    font-size: 14px;
}

/* ===== 动画 ===== */
@keyframes float {
    0%, 100% { transform: translateY(0); }
    50% { transform: translateY(-20px); }
}

@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(30px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

@keyframes gradientShift {
    0%, 100% { transform: translate(0, 0); }
    50% { transform: translate(-5%, 5%); }
}

/* ===== Toast 通知 ===== */
.toast {
    position: fixed;
    top: 100px;
    right: 24px;
    padding: 16px 24px;
    border-radius: var(--radius-sm);
    font-size: 14px;
    font-weight: 500;
    z-index: 9999;
    opacity: 0;
    transform: translateX(100px);
    transition: all 0.4s ease;
}

.toast.show {
    opacity: 1;
    transform: translateX(0);
}

.toast.success {
    background: #10B981;
    color: white;
    box-shadow: 0 8px 24px rgba(16, 185, 129, 0.3);
}

.toast.error {
    background: #EF4444;
    color: white;
    box-shadow: 0 8px 24px rgba(239, 68, 68, 0.3);
}

/* ===== 响应式设计 ===== */
@media (max-width: 1024px) {
    .hero-title {
        font-size: 48px;
    }

    .features-grid {
        grid-template-columns: repeat(2, 1fr);
    }

    .pricing-grid {
        grid-template-columns: 1fr;
        max-width: 400px;
        margin: 0 auto;
    }

    .pricing-card.popular {
        transform: none;
    }

    .pricing-card.popular:hover {
        transform: translateY(-8px);
    }

    .footer-grid {
        grid-template-columns: repeat(2, 1fr);
    }
}

@media (max-width: 768px) {
    .nav-links {
        display: none;
        position: absolute;
        top: 72px;
        left: 0;
        right: 0;
        background: rgba(10, 10, 26, 0.98);
        backdrop-filter: blur(20px);
        flex-direction: column;
        padding: 24px;
        gap: 16px;
        border-bottom: 1px solid var(--border-color);
    }

    .nav-links.active {
        display: flex;
    }

    .menu-toggle {
        display: flex;
    }

    .hero .container {
        grid-template-columns: 1fr;
        text-align: center;
    }

    .hero-title {
        font-size: 36px;
    }

    .hero-stats {
        justify-content: center;
        flex-wrap: wrap;
        gap: 24px;
    }

    .hero-visual {
        display: none;
    }

    .hero-actions {
        justify-content: center;
        flex-direction: column;
        align-items: center;
    }

    .section-header h2 {
        font-size: 32px;
    }

    .register-card {
        padding: 32px 24px;
    }

    .form-row {
        grid-template-columns: 1fr;
    }

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

    .footer-grid {
        grid-template-columns: 1fr;
        gap: 32px;
    }
}

@media (max-width: 480px) {
    .hero-title {
        font-size: 28px;
    }

    .hero-desc {
        font-size: 16px;
    }

    .stat-number {
        font-size: 22px;
    }

    .price .amount {
        font-size: 36px;
    }
}