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

body {
    /* 字体方案：优先使用国内主流中文字体，回退到系统默认 */
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Microsoft YaHei", "微软雅黑", "Helvetica Neue", Helvetica, Arial, sans-serif;
    background-color: #F0F7FF;
    color: #1A3A5C;
    line-height: 1.5;
}

:root {
    --primary: #4AA8E8;
    --primary-light: #7DC4FF;
    --accent-orange: #FF8C42;
    --accent-purple: #7B61FF;
    --bg-light: #F0F7FF;
    --card-white: #FFFFFF;
    --text-dark: #1A3A5C;
    --text-medium: #5A7A9A;
    --border-light: #C8E1FA;
    --gradient-blue: linear-gradient(135deg, #4AA8E8, #7DC4FF);
    --gradient-deep: linear-gradient(135deg, #1A3A5C, #4AA8E8);
    --shadow-sm: 0 4px 12px rgba(0, 0, 0, 0.04);
    --shadow-hover: 0 20px 30px -12px rgba(74, 168, 232, 0.25);
    --radius-card: 20px;
    --radius-btn: 40px;
}

.container {
    max-width: 1280px;
    margin: 0 auto;
    padding: 0 24px;
}

@media (max-width: 768px) {
    .container { padding: 0 20px; }
    :root { --radius-card: 18px; }
}

/* 导航栏 */
.navbar {
    background: rgba(255, 255, 255, 0.96);
    backdrop-filter: blur(12px);
    position: sticky;
    top: 0;
    z-index: 100;
    border-bottom: 1px solid var(--border-light);
    padding: 12px 0;
}

.nav-inner {
    display: flex;
    align-items: center;
    justify-content: space-between;
    flex-wrap: wrap;
    gap: 12px;
}

.logo {
    font-size: 1.6rem;
    font-weight: 800;
    background: var(--gradient-blue);
    background-clip: text;
    -webkit-background-clip: text;
    color: transparent;
}

.logo span { color: var(--accent-orange); }

.nav-links {
    display: flex;
    gap: 28px;
    list-style: none;
    flex-wrap: wrap;
}

.nav-links a {
    text-decoration: none;
    font-weight: 500;
    color: var(--text-dark);
    transition: 0.2s;
}

.nav-links a:hover, .nav-links a.active {
    color: var(--primary);
    border-bottom: 2px solid var(--primary);
    padding-bottom: 4px;
}

.btn {
    display: inline-block;
    padding: 10px 24px;
    border-radius: var(--radius-btn);
    font-weight: 600;
    text-decoration: none;
    transition: 0.2s;
    cursor: pointer;
    border: none;
    font-size: 0.95rem;
    text-align: center;
}

.btn-primary {
    background: var(--accent-orange);
    color: white;
    box-shadow: 0 4px 8px rgba(255, 140, 66, 0.2);
}

.btn-primary:hover {
    background: #e0772e;
    transform: translateY(-2px);
}

.btn-outline {
    background: transparent;
    border: 1.5px solid var(--primary);
    color: var(--primary);
}

.btn-outline:hover {
    background: var(--primary);
    color: white;
}

.card {
    background: var(--card-white);
    border-radius: var(--radius-card);
    border: 1px solid var(--border-light);
    padding: 24px;
    transition: 0.25s;
    box-shadow: var(--shadow-sm);
    height: 100%;
}

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

section { padding: 70px 0; }

@media (max-width: 768px) { section { padding: 50px 0; } }

.section-title {
    font-size: 2.2rem;
    font-weight: 700;
    margin-bottom: 16px;
    text-align: center;
}

.section-sub {
    text-align: center;
    color: var(--text-medium);
    max-width: 680px;
    margin: 0 auto 48px auto;
    font-size: 1.1rem;
}

@media (max-width: 768px) {
    .section-title { font-size: 1.8rem; }
    .section-sub { font-size: 1rem; }
}

.grid-4, .grid-3 {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
    gap: 32px;
}

.icon-symbol { font-size: 2.4rem; margin-bottom: 16px; }

.tag {
    background: #EFF5FF;
    color: var(--primary);
    border-radius: 40px;
    padding: 4px 12px;
    font-size: 0.75rem;
    font-weight: 600;
    display: inline-block;
    margin-bottom: 12px;
}

.hero {
    background: linear-gradient(125deg, #E9F3FF, #FFFFFF);
}

.hero h1 {
    font-size: 3rem;
    font-weight: 800;
    line-height: 1.2;
}

@media (max-width: 768px) { .hero h1 { font-size: 2.2rem; } }

.path-step {
    display: flex;
    gap: 24px;
    margin-bottom: 28px;
    flex-wrap: wrap;
    background: white;
    border-radius: 24px;
    border-left: 6px solid var(--primary);
    padding: 20px;
}

.step-number {
    font-size: 2.5rem;
    font-weight: 800;
    color: var(--primary-light);
    min-width: 70px;
}

.step-content h3 { font-size: 1.5rem; margin-bottom: 8px; }

@media (max-width: 680px) {
    .path-step { flex-direction: column; }
    .step-number { font-size: 2rem; }
}

.works-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
    gap: 28px;
}

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

label { font-weight: 500; margin-bottom: 6px; display: block; }

input, select, textarea {
    width: 100%;
    padding: 12px 16px;
    border-radius: 16px;
    border: 1px solid var(--border-light);
    font-family: inherit;
}

input:focus, select:focus, textarea:focus {
    outline: none;
    border-color: var(--primary);
    box-shadow: 0 0 0 3px rgba(74,168,232,0.2);
}

.radio-group {
    display: flex;
    gap: 20px;
    align-items: center;
    flex-wrap: wrap;
}

footer {
    background: var(--text-dark);
    color: #cbdbe0;
    padding: 48px 0 32px;
    margin-top: 40px;
}

.flex-between {
    display: flex;
    justify-content: space-between;
    flex-wrap: wrap;
    gap: 20px;
}

.footer-bottom {
    text-align: center;
    font-size: 0.85rem;
    border-top: 1px solid rgba(255,255,255,0.1);
    margin-top: 32px;
    padding-top: 24px;
}

@media (max-width: 720px) {
    .nav-inner { flex-direction: column; align-items: center; }
    .nav-links { justify-content: center; gap: 18px; }
}

.page-section { display: none; }
.page-section.active-page { display: block; }

.btn-group { display: flex; gap: 16px; flex-wrap: wrap; }

.principle-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 32px;
    margin-top: 32px;
}

.highlight-text { color: var(--accent-orange); font-weight: 700; }

.quote-icon { font-size: 2.5rem; color: var(--primary-light); margin-bottom: 12px; }