/* ===== 全局重置 & 基础 ===== */
*,
*::before,
*::after {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

:root {
    --primary: #0d9488;
    --primary-dark: #0f766e;
    --primary-light: #14b8a6;
    --secondary: #0891b2;
    --accent: #f59e0b;
    --bg: #f0fdf4;
    --bg-light: #f8fafc;
    --text: #1e293b;
    --text-light: #64748b;
    --white: #ffffff;
    --shadow: 0 4px 20px rgba(13, 148, 136, 0.12);
    --shadow-hover: 0 12px 40px rgba(13, 148, 136, 0.20);
    --radius: 16px;
    --transition: 0.3s ease;
    --font: 'Inter', system-ui, -apple-system, sans-serif;
}

html {
    scroll-behavior: smooth;
}

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

a {
    text-decoration: none;
    color: inherit;
}

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

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

/* ===== 导航栏 ===== */
.navbar {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    z-index: 1000;
    background: rgba(240, 253, 244, 0.7);
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    border-bottom: 1px solid rgba(13, 148, 136, 0.08);
    transition: background var(--transition), box-shadow var(--transition);
}

.navbar.scrolled {
    background: rgba(240, 253, 244, 0.95);
    box-shadow: 0 2px 20px rgba(13, 148, 136, 0.08);
}

.nav-container {
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 70px;
}

.logo {
    display: flex;
    align-items: center;
    gap: 10px;
    font-size: 1.3rem;
    font-weight: 700;
    color: var(--primary-dark);
}

.logo i {
    font-size: 1.6rem;
    color: var(--primary);
}

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

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

.nav-links a::after {
    content: '';
    position: absolute;
    bottom: -4px;
    left: 0;
    width: 0;
    height: 2px;
    background: var(--primary);
    transition: width var(--transition);
    border-radius: 2px;
}

.nav-links a:hover,
.nav-links a.active {
    color: var(--primary-dark);
}

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

.menu-toggle {
    display: none;
    background: none;
    border: none;
    font-size: 1.5rem;
    color: var(--primary-dark);
    cursor: pointer;
    padding: 4px;
}

/* ===== Hero ===== */
.hero {
    padding: 120px 0 80px;
    background: linear-gradient(135deg, #ccfbf1, #f0fdf4, #e0f2fe);
    position: relative;
    overflow: hidden;
}

.hero-content {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 40px;
    flex-wrap: wrap;
}

.hero-text {
    flex: 1 1 500px;
}

.hero-text h1 {
    font-size: 3.2rem;
    font-weight: 700;
    color: var(--primary-dark);
    line-height: 1.2;
    margin-bottom: 16px;
}

.hero-text p {
    font-size: 1.2rem;
    color: var(--text-light);
    margin-bottom: 32px;
}

.hero-buttons {
    display: flex;
    gap: 16px;
    flex-wrap: wrap;
}

.hero-image {
    flex: 0 0 260px;
    display: flex;
    justify-content: center;
    align-items: center;
}

.hero-image i {
    font-size: 12rem;
    color: var(--primary);
    opacity: 0.2;
    animation: float 4s ease-in-out infinite;
}

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

.hero-wave {
    position: absolute;
    bottom: -2px;
    left: 0;
    width: 100%;
    line-height: 0;
}

.hero-wave svg {
    display: block;
    width: 100%;
    height: 80px;
}

/* ===== 通用按钮 ===== */
.btn {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 14px 28px;
    border-radius: 50px;
    font-weight: 600;
    font-size: 1rem;
    border: none;
    cursor: pointer;
    transition: all var(--transition);
    text-decoration: none;
}

.btn-primary {
    background: var(--primary);
    color: var(--white);
    box-shadow: 0 4px 14px rgba(13, 148, 136, 0.4);
}

.btn-primary:hover {
    background: var(--primary-dark);
    transform: translateY(-2px);
    box-shadow: 0 8px 24px rgba(13, 148, 136, 0.5);
}

.btn-secondary {
    background: var(--white);
    color: var(--primary-dark);
    border: 2px solid var(--primary);
}

.btn-secondary:hover {
    background: var(--primary);
    color: var(--white);
    transform: translateY(-2px);
}

.btn-block {
    width: 100%;
    justify-content: center;
}

/* ===== 通用 Section ===== */
.section {
    padding: 80px 0;
}

.bg-light {
    background: var(--bg-light);
}

.section-header {
    text-align: center;
    margin-bottom: 48px;
}

.section-tag {
    display: inline-block;
    background: var(--primary);
    color: var(--white);
    padding: 4px 16px;
    border-radius: 50px;
    font-size: 0.85rem;
    font-weight: 600;
    letter-spacing: 0.5px;
    margin-bottom: 12px;
}

.section-header h2 {
    font-size: 2.2rem;
    font-weight: 700;
    color: var(--primary-dark);
    margin-bottom: 8px;
}

.section-header p {
    color: var(--text-light);
    font-size: 1.1rem;
}

/* ===== 卡片网格 ===== */
.card-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
    gap: 24px;
}

.card {
    background: var(--white);
    border-radius: var(--radius);
    padding: 28px 24px;
    box-shadow: var(--shadow);
    transition: all var(--transition);
    cursor: default;
    border: 1px solid rgba(13, 148, 136, 0.06);
}

.card:hover {
    transform: translateY(-6px);
    box-shadow: var(--shadow-hover);
}

.card-icon {
    width: 52px;
    height: 52px;
    border-radius: 12px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.5rem;
    color: var(--white);
    margin-bottom: 16px;
}

.card h3 {
    font-size: 1.2rem;
    font-weight: 600;
    margin-bottom: 8px;
    color: var(--text);
}

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

/* ===== 症状自测 ===== */
.symptom-checker {
    background: var(--white);
    border-radius: var(--radius);
    padding: 36px;
    box-shadow: var(--shadow);
    max-width: 700px;
    margin: 0 auto;
}

.symptom-options {
    display: flex;
    flex-wrap: wrap;
    gap: 12px;
    margin-bottom: 24px;
}

.symptom-tag {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    padding: 10px 20px;
    border-radius: 50px;
    border: 2px solid var(--primary);
    background: var(--white);
    color: var(--primary-dark);
    font-weight: 500;
    font-size: 0.9rem;
    cursor: pointer;
    transition: all var(--transition);
    user-select: none;
}

.symptom-tag:hover {
    border-color: var(--primary-light);
    background: #f0fdfa;
}

.symptom-tag.active {
    background: var(--primary);
    color: var(--white);
    border-color: var(--primary);
}

.symptom-result {
    background: #f0fdfa;
    border-radius: 12px;
    padding: 20px;
    display: flex;
    align-items: center;
    gap: 16px;
    border-left: 4px solid var(--primary);
    min-height: 80px;
}

.symptom-result i {
    font-size: 2rem;
    color: var(--primary);
    flex-shrink: 0;
}

.symptom-result p {
    color: var(--text);
    font-weight: 500;
}

/* ===== 治疗方案 ===== */
.treatment-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(260px, 1fr));
    gap: 24px;
}

.treatment-card {
    background: var(--white);
    border-radius: var(--radius);
    padding: 28px 24px;
    box-shadow: var(--shadow);
    transition: all var(--transition);
    border: 1px solid rgba(13, 148, 136, 0.06);
    text-align: center;
}

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

.treatment-card i {
    font-size: 2.4rem;
    color: var(--primary);
    margin-bottom: 16px;
}

.treatment-card h3 {
    font-size: 1.15rem;
    font-weight: 600;
    margin-bottom: 8px;
}

.treatment-card p {
    color: var(--text-light);
    font-size: 0.9rem;
    line-height: 1.6;
}

/* ===== 专家团队 ===== */
.expert-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(220px, 1fr));
    gap: 24px;
}

.expert-card {
    background: var(--white);
    border-radius: var(--radius);
    padding: 28px 20px;
    text-align: center;
    box-shadow: var(--shadow);
    transition: all var(--transition);
    border: 1px solid rgba(13, 148, 136, 0.06);
}

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

.expert-avatar {
    width: 72px;
    height: 72px;
    border-radius: 50%;
    background: linear-gradient(135deg, var(--primary-light), var(--primary));
    display: flex;
    align-items: center;
    justify-content: center;
    margin: 0 auto 16px;
    font-size: 2rem;
    color: var(--white);
    font-weight: 700;
}

.expert-card h3 {
    font-size: 1.1rem;
    font-weight: 600;
    margin-bottom: 4px;
}

.expert-card .title {
    color: var(--primary);
    font-weight: 600;
    font-size: 0.9rem;
    margin-bottom: 8px;
}

.expert-card p {
    color: var(--text-light);
    font-size: 0.85rem;
}

/* ===== 联系表单 ===== */
.contact-wrapper {
    display: flex;
    gap: 40px;
    flex-wrap: wrap;
    align-items: flex-start;
    max-width: 900px;
    margin: 0 auto;
}

.contact-form {
    flex: 1 1 400px;
    background: var(--white);
    padding: 36px;
    border-radius: var(--radius);
    box-shadow: var(--shadow);
}

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

.form-group input,
.form-group textarea {
    width: 100%;
    padding: 14px 18px;
    border: 2px solid #e2e8f0;
    border-radius: 12px;
    font-size: 1rem;
    font-family: var(--font);
    transition: border-color var(--transition), box-shadow var(--transition);
    background: var(--bg-light);
    outline: none;
}

.form-group input:focus,
.form-group textarea:focus {
    border-color: var(--primary);
    box-shadow: 0 0 0 4px rgba(13, 148, 136, 0.12);
}

.form-group .error-msg {
    display: block;
    color: #dc2626;
    font-size: 0.85rem;
    margin-top: 4px;
    min-height: 20px;
}

.contact-info {
    flex: 0 0 240px;
    display: flex;
    flex-direction: column;
    gap: 20px;
    padding-top: 8px;
}

.info-item {
    display: flex;
    align-items: center;
    gap: 12px;
    color: var(--text-light);
    font-size: 0.95rem;
}

.info-item i {
    width: 40px;
    height: 40px;
    border-radius: 50%;
    background: var(--primary);
    color: var(--white);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1rem;
    flex-shrink: 0;
}

/* ===== Toast ===== */
.toast {
    position: fixed;
    bottom: 30px;
    right: 30px;
    background: var(--primary-dark);
    color: var(--white);
    padding: 16px 28px;
    border-radius: 12px;
    font-weight: 600;
    box-shadow: 0 8px 30px rgba(0,0,0,0.2);
    opacity: 0;
    transform: translateY(20px);
    transition: all 0.4s ease;
    pointer-events: none;
    z-index: 9999;
}

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

/* ===== 页脚 ===== */
.footer {
    background: var(--primary-dark);
    color: var(--white);
    padding: 40px 0;
    text-align: center;
}

.footer-content {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 8px;
}

.footer-brand {
    display: flex;
    align-items: center;
    gap: 10px;
    font-size: 1.2rem;
    font-weight: 700;
}

.footer-brand i {
    font-size: 1.4rem;
}

.footer-text {
    color: rgba(255,255,255,0.7);
    font-size: 0.9rem;
}

/* ===== 响应式 ===== */
@media (max-width: 768px) {
    .nav-links {
        position: fixed;
        top: 70px;
        left: 0;
        right: 0;
        background: rgba(240, 253, 244, 0.98);
        backdrop-filter: blur(12px);
        flex-direction: column;
        align-items: center;
        gap: 0;
        padding: 20px 0;
        box-shadow: 0 8px 24px rgba(0,0,0,0.06);
        transform: translateY(-120%);
        transition: transform 0.4s ease;
        border-bottom: 1px solid rgba(13, 148, 136, 0.08);
    }

    .nav-links.open {
        transform: translateY(0);
    }

    .nav-links a {
        padding: 14px 0;
        width: 100%;
        text-align: center;
        border-bottom: 1px solid rgba(13, 148, 136, 0.04);
    }

    .menu-toggle {
        display: block;
    }

    .hero-text h1 {
        font-size: 2.2rem;
    }

    .hero-image {
        display: none;
    }

    .section-header h2 {
        font-size: 1.8rem;
    }

    .contact-wrapper {
        flex-direction: column;
    }

    .contact-info {
        flex-direction: row;
        flex-wrap: wrap;
        justify-content: center;
    }
}

@media (max-width: 480px) {
    .hero {
        padding: 100px 0 60px;
    }

    .hero-text h1 {
        font-size: 1.8rem;
    }

    .hero-text p {
        font-size: 1rem;
    }

    .btn {
        padding: 12px 22px;
        font-size: 0.9rem;
    }

    .card-grid,
    .treatment-grid,
    .expert-grid {
        grid-template-columns: 1fr;
    }

    .symptom-checker {
        padding: 20px;
    }

    .contact-form {
        padding: 24px;
    }
}