/* ===== 设计令牌 ===== */
:root {
    --primary: #3b4cb8;
    --primary-dark: #2d3a8c;
    --primary-light: #eef0ff;
    --accent: #f59e0b;
    --accent-light: #fef3c7;
    --text-primary: #1a1a2e;
    --text-secondary: #64748b;
    --text-light: #94a3b8;
    --bg-white: #ffffff;
    --bg-light: #f8fafc;
    --bg-gray: #f1f5f9;
    --border: #e2e8f0;
    --border-light: #f1f5f9;
    --success: #10b981;
    --error: #ef4444;
    --warning: #f59e0b;
    --shadow-sm: 0 1px 2px rgba(0,0,0,0.05);
    --shadow: 0 4px 6px -1px rgba(0,0,0,0.07), 0 2px 4px -2px rgba(0,0,0,0.05);
    --shadow-md: 0 10px 15px -3px rgba(0,0,0,0.08), 0 4px 6px -4px rgba(0,0,0,0.05);
    --shadow-lg: 0 20px 25px -5px rgba(0,0,0,0.08), 0 8px 10px -6px rgba(0,0,0,0.04);
    --radius: 12px;
    --radius-sm: 8px;
    --radius-lg: 16px;
    --transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

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

html { scroll-behavior: smooth; font-size: 16px; }

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'PingFang SC', 'Hiragino Sans GB', 'Microsoft YaHei', sans-serif;
    color: var(--text-primary);
    background: var(--bg-white);
    line-height: 1.6;
    -webkit-font-smoothing: antialiased;
}

a { color: var(--primary); text-decoration: none; transition: var(--transition); }
a:hover { color: var(--primary-dark); }

img { max-width: 100%; height: auto; }

/* ===== 导航栏 ===== */
.navbar {
    position: fixed; top: 0; left: 0; right: 0; z-index: 1000;
    background: rgba(255,255,255,0.95);
    backdrop-filter: blur(20px);
    border-bottom: 1px solid var(--border-light);
    padding: 0 40px;
    height: 64px;
    display: flex; align-items: center; justify-content: space-between;
    transition: var(--transition);
}

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

.navbar-brand {
    display: flex; align-items: center; gap: 10px;
    font-size: 18px; font-weight: 700; color: var(--text-primary);
}

.navbar-brand svg { width: 28px; height: 28px; }

.navbar-links { display: flex; align-items: center; gap: 24px; }

.navbar-links a {
    font-size: 14px; color: var(--text-secondary);
    display: flex; align-items: center; gap: 6px;
    padding: 6px 0;
}
.navbar-links a:hover { color: var(--primary); }

.btn-nav {
    background: var(--primary); color: white !important;
    padding: 8px 20px; border-radius: 20px;
    font-size: 14px; font-weight: 500;
    display: flex; align-items: center; gap: 6px;
    transition: var(--transition);
}
.btn-nav:hover { background: var(--primary-dark); transform: translateY(-1px); box-shadow: var(--shadow); }

/* ===== Hero 区域 ===== */
.hero {
    min-height: 100vh;
    display: flex; flex-direction: column;
    align-items: center; justify-content: center;
    text-align: center;
    padding: 120px 20px 80px;
    background: linear-gradient(180deg, var(--bg-white) 0%, var(--bg-light) 100%);
}

.hero-badge {
    display: inline-flex; align-items: center; gap: 8px;
    background: var(--bg-light); border: 1px solid var(--border);
    padding: 6px 16px; border-radius: 20px;
    font-size: 13px; color: var(--text-secondary);
    margin-bottom: 32px;
}
.hero-badge svg { color: var(--accent); }

.hero h1 {
    font-size: 42px; font-weight: 800;
    line-height: 1.3; margin-bottom: 20px;
    color: var(--text-primary);
    max-width: 600px;
}

.hero p {
    font-size: 16px; color: var(--text-secondary);
    line-height: 1.8; max-width: 500px;
    margin-bottom: 40px;
}

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

.btn-primary {
    background: var(--primary); color: white;
    padding: 12px 32px; border-radius: 24px;
    font-size: 15px; font-weight: 600;
    display: inline-flex; align-items: center; gap: 8px;
    border: none; cursor: pointer;
    transition: var(--transition);
}
.btn-primary:hover { background: var(--primary-dark); transform: translateY(-2px); box-shadow: var(--shadow-md); color: white; }

.btn-outline {
    background: var(--bg-white); color: var(--text-primary);
    padding: 12px 32px; border-radius: 24px;
    font-size: 15px; font-weight: 500;
    display: inline-flex; align-items: center; gap: 8px;
    border: 1px solid var(--border);
    cursor: pointer; transition: var(--transition);
}
.btn-outline:hover { border-color: var(--primary); color: var(--primary); transform: translateY(-2px); }

/* ===== 通用区块 ===== */
.section {
    padding: 80px 20px;
    max-width: 1100px;
    margin: 0 auto;
}

.section-title {
    text-align: center;
    font-size: 32px; font-weight: 700;
    margin-bottom: 12px;
}

.section-desc {
    text-align: center;
    font-size: 15px; color: var(--text-secondary);
    margin-bottom: 48px;
    max-width: 600px; margin-left: auto; margin-right: auto;
}

/* ===== 三步流程 ===== */
.steps {
    display: grid; grid-template-columns: repeat(3, 1fr);
    gap: 40px; padding: 60px 20px;
    max-width: 900px; margin: 0 auto;
}

.step { text-align: center; }

.step-icon {
    width: 64px; height: 64px; margin: 0 auto 16px;
    display: flex; align-items: center; justify-content: center;
    font-size: 32px;
}

.step h3 { font-size: 18px; font-weight: 600; margin-bottom: 8px; }
.step p { font-size: 14px; color: var(--text-secondary); line-height: 1.6; }

/* ===== 技能卡片 ===== */
.skills-grid {
    display: grid; grid-template-columns: repeat(2, 1fr);
    gap: 24px; max-width: 1100px; margin: 0 auto;
    padding: 0 20px;
}

.skill-card {
    background: var(--bg-white);
    border: 1px solid var(--border);
    border-radius: var(--radius-lg);
    padding: 32px;
    transition: var(--transition);
    display: flex; flex-direction: column;
    text-decoration: none; color: inherit;
}
.skill-card:hover {
    border-color: var(--primary);
    box-shadow: var(--shadow-lg);
    transform: translateY(-4px);
    color: inherit;
}

.skill-card-icon {
    width: 48px; height: 48px;
    background: var(--primary-light);
    border-radius: var(--radius-sm);
    display: flex; align-items: center; justify-content: center;
    font-size: 24px; margin-bottom: 16px;
}

.skill-card h3 { font-size: 20px; font-weight: 600; margin-bottom: 12px; }
.skill-card p { font-size: 14px; color: var(--text-secondary); line-height: 1.7; margin-bottom: 16px; flex: 1; }

.skill-tags { display: flex; flex-wrap: wrap; gap: 8px; }
.skill-tag {
    background: var(--bg-gray);
    padding: 4px 12px; border-radius: 12px;
    font-size: 12px; color: var(--text-secondary);
}

/* ===== 平台支持 ===== */
.platforms-grid {
    display: grid; grid-template-columns: repeat(auto-fill, minmax(160px, 1fr));
    gap: 20px; max-width: 1100px; margin: 0 auto;
    padding: 0 20px;
}

.platform-card {
    background: var(--bg-white);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    padding: 24px 16px;
    text-align: center;
    transition: var(--transition);
}
.platform-card:hover { border-color: var(--primary); box-shadow: var(--shadow); transform: translateY(-2px); }

.platform-card-icon { font-size: 40px; margin-bottom: 12px; }
.platform-card h4 { font-size: 14px; font-weight: 600; margin-bottom: 6px; }
.platform-card p { font-size: 12px; color: var(--text-secondary); }

/* ===== 页脚 ===== */
.footer {
    text-align: center;
    padding: 32px 20px;
    border-top: 1px solid var(--border-light);
    font-size: 13px; color: var(--text-light);
}

/* ===== 详情页 ===== */
.detail-hero {
    padding: 100px 20px 40px;
    text-align: center;
    background: linear-gradient(180deg, var(--bg-white) 0%, var(--bg-light) 100%);
}

.detail-hero .back-link {
    display: inline-flex; align-items: center; gap: 6px;
    font-size: 14px; color: var(--primary);
    margin-bottom: 24px;
}

.detail-hero h1 { font-size: 36px; font-weight: 800; margin-bottom: 16px; }
.detail-hero p {
    font-size: 15px; color: var(--text-secondary);
    max-width: 600px; margin: 0 auto 20px;
    line-height: 1.7;
}

.detail-meta {
    display: flex; justify-content: center; gap: 24px;
    font-size: 13px; color: var(--text-light);
    flex-wrap: wrap;
}
.detail-meta span { display: flex; align-items: center; gap: 4px; }

/* ===== 内容卡片 ===== */
.content-card {
    background: var(--bg-white);
    border: 1px solid var(--border);
    border-radius: var(--radius-lg);
    padding: 32px;
    margin: 24px auto;
    max-width: 800px;
}

.content-card h2 {
    font-size: 20px; font-weight: 700;
    margin-bottom: 24px;
    display: flex; align-items: center; gap: 8px;
}

/* ===== 功能特性网格 ===== */
.features-grid {
    display: grid; grid-template-columns: repeat(2, 1fr);
    gap: 16px;
}

.feature-item {
    padding: 20px;
    border-radius: var(--radius-sm);
    background: var(--bg-light);
    transition: var(--transition);
}
.feature-item:hover { background: var(--primary-light); }

.feature-item h4 {
    font-size: 15px; font-weight: 600;
    margin-bottom: 6px;
    display: flex; align-items: center; gap: 6px;
}
.feature-item p { font-size: 13px; color: var(--text-secondary); }

/* ===== Tab 切换 ===== */
.tab-nav {
    display: flex; gap: 4px;
    border-bottom: 2px solid var(--border);
    margin-bottom: 24px;
    overflow-x: auto;
}

.tab-btn {
    padding: 10px 20px;
    font-size: 14px; font-weight: 500;
    color: var(--text-secondary);
    background: none; border: none;
    cursor: pointer;
    border-bottom: 2px solid transparent;
    margin-bottom: -2px;
    white-space: nowrap;
    transition: var(--transition);
}
.tab-btn:hover { color: var(--primary); }
.tab-btn.active {
    color: var(--primary);
    border-bottom-color: var(--primary);
    font-weight: 600;
}

.tab-content { display: none; }
.tab-content.active { display: block; }

/* ===== 表单 ===== */
.form-group { margin-bottom: 20px; }

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

.form-input, .form-select, .form-textarea {
    width: 100%;
    padding: 10px 14px;
    border: 1px solid var(--border);
    border-radius: var(--radius-sm);
    font-size: 14px;
    color: var(--text-primary);
    background: var(--bg-white);
    transition: var(--transition);
    font-family: inherit;
}
.form-input:focus, .form-select:focus, .form-textarea:focus {
    outline: none;
    border-color: var(--primary);
    box-shadow: 0 0 0 3px rgba(59, 76, 184, 0.1);
}

.form-textarea { resize: vertical; min-height: 100px; }

.form-row {
    display: grid; grid-template-columns: 1fr 1fr;
    gap: 16px;
}

.form-hint { font-size: 12px; color: var(--text-light); margin-top: 4px; }

.btn-submit {
    background: var(--primary); color: white;
    padding: 12px 28px; border-radius: 24px;
    font-size: 15px; font-weight: 600;
    border: none; cursor: pointer;
    display: inline-flex; align-items: center; gap: 8px;
    transition: var(--transition);
    margin-top: 8px;
}
.btn-submit:hover { background: var(--primary-dark); transform: translateY(-1px); box-shadow: var(--shadow); }
.btn-submit:disabled {
    opacity: 0.7; cursor: not-allowed; transform: none;
}
.btn-submit .spinner {
    width: 16px; height: 16px;
    border: 2px solid rgba(255,255,255,0.3);
    border-top-color: white;
    border-radius: 50%;
    animation: spin 0.8s linear infinite;
    display: none;
}
.btn-submit.loading .spinner { display: inline-block; }
.btn-submit.loading .btn-text { display: none; }
.btn-submit.loading .btn-loading-text { display: inline; }
.btn-submit .btn-loading-text { display: none; }

@keyframes spin { to { transform: rotate(360deg); } }

/* ===== 结果展示 ===== */
.result-container {
    margin-top: 24px;
    display: none;
}
.result-container.show { display: block; }

.result-box {
    background: var(--bg-light);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    overflow: hidden;
}

.result-header {
    display: flex; align-items: center; justify-content: space-between;
    padding: 12px 16px;
    background: var(--text-primary);
    color: white;
    font-size: 13px; font-weight: 500;
}

.btn-copy {
    background: rgba(255,255,255,0.15);
    color: white; border: none;
    padding: 4px 12px; border-radius: 4px;
    font-size: 12px; cursor: pointer;
    transition: var(--transition);
}
.btn-copy:hover { background: rgba(255,255,255,0.25); }

.result-body {
    padding: 20px;
    max-height: 600px;
    overflow-y: auto;
    font-size: 14px;
    line-height: 1.8;
}

/* ===== Markdown 渲染 ===== */
.result-body h1 { font-size: 22px; font-weight: 700; margin: 20px 0 12px; padding-bottom: 8px; border-bottom: 2px solid var(--border); }
.result-body h2 { font-size: 19px; font-weight: 700; margin: 18px 0 10px; color: var(--primary-dark); }
.result-body h3 { font-size: 16px; font-weight: 600; margin: 14px 0 8px; }
.result-body h4 { font-size: 15px; font-weight: 600; margin: 12px 0 6px; }
.result-body p { margin: 8px 0; }
.result-body ul, .result-body ol { padding-left: 24px; margin: 8px 0; }
.result-body li { margin: 4px 0; }
.result-body strong { color: var(--text-primary); font-weight: 600; }
.result-body em { font-style: italic; color: var(--text-secondary); }
.result-body blockquote {
    border-left: 3px solid var(--primary);
    padding: 8px 16px; margin: 12px 0;
    background: var(--primary-light);
    border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
}
.result-body code {
    background: rgba(59, 76, 184, 0.08);
    padding: 2px 6px; border-radius: 4px;
    font-size: 13px; font-family: 'Menlo', 'Consolas', monospace;
}
.result-body pre {
    background: var(--text-primary);
    color: #e2e8f0; padding: 16px;
    border-radius: var(--radius-sm);
    overflow-x: auto; margin: 12px 0;
}
.result-body pre code { background: none; color: inherit; padding: 0; }
.result-body table {
    width: 100%; border-collapse: collapse;
    margin: 12px 0; font-size: 13px;
}
.result-body th, .result-body td {
    border: 1px solid var(--border);
    padding: 8px 12px; text-align: left;
}
.result-body th { background: var(--bg-gray); font-weight: 600; }
.result-body hr { border: none; border-top: 1px solid var(--border); margin: 16px 0; }

/* ===== 示例代码块 ===== */
.example-block {
    background: var(--text-primary);
    color: #e2e8f0;
    padding: 20px;
    border-radius: var(--radius);
    font-family: 'Menlo', 'Consolas', monospace;
    font-size: 13px;
    line-height: 1.7;
    overflow-x: auto;
    white-space: pre-wrap;
    position: relative;
    margin: 16px 0;
}

.example-block .copy-btn {
    position: absolute; top: 8px; right: 8px;
    background: rgba(255,255,255,0.15);
    color: white; border: none;
    padding: 4px 12px; border-radius: 4px;
    font-size: 12px; cursor: pointer;
}

/* ===== 表格样式 ===== */
.info-table {
    width: 100%; border-collapse: collapse;
    margin: 16px 0; font-size: 14px;
}
.info-table th, .info-table td {
    border: 1px solid var(--border);
    padding: 10px 14px; text-align: left;
}
.info-table th { background: var(--bg-gray); font-weight: 600; font-size: 13px; }
.info-table td { color: var(--text-secondary); }

/* ===== FAB 法则展示 ===== */
.fab-cards {
    display: grid; grid-template-columns: repeat(3, 1fr);
    gap: 16px; margin: 16px 0;
}
.fab-card {
    text-align: center; padding: 20px;
    background: var(--bg-light);
    border-radius: var(--radius-sm);
}
.fab-card .letter {
    width: 40px; height: 40px;
    background: var(--primary);
    color: white; border-radius: 50%;
    display: flex; align-items: center; justify-content: center;
    font-size: 18px; font-weight: 700;
    margin: 0 auto 8px;
}
.fab-card h4 { font-size: 14px; font-weight: 600; margin-bottom: 4px; }
.fab-card p { font-size: 12px; color: var(--text-secondary); }

/* ===== 语气风格卡片 ===== */
.tone-grid {
    display: grid; grid-template-columns: repeat(auto-fill, minmax(140px, 1fr));
    gap: 12px; margin: 16px 0;
}
.tone-card {
    padding: 16px; text-align: center;
    background: var(--bg-light);
    border-radius: var(--radius-sm);
    border: 1px solid var(--border);
    transition: var(--transition);
}
.tone-card:hover { border-color: var(--primary); background: var(--primary-light); }
.tone-card .emoji { font-size: 24px; margin-bottom: 6px; }
.tone-card h4 { font-size: 13px; font-weight: 600; }
.tone-card p { font-size: 11px; color: var(--text-secondary); margin-top: 2px; }

/* ===== Toast 提示 ===== */
.toast {
    position: fixed; top: 80px; right: 20px; z-index: 9999;
    background: var(--text-primary); color: white;
    padding: 12px 24px; border-radius: var(--radius-sm);
    font-size: 14px; box-shadow: var(--shadow-lg);
    transform: translateX(120%);
    transition: transform 0.3s ease;
}
.toast.show { transform: translateX(0); }
.toast.success { background: var(--success); }
.toast.error { background: var(--error); }

/* ===== 错误结果 ===== */
.result-error {
    background: #fef2f2;
    border: 1px solid #fecaca;
    border-radius: var(--radius-sm);
    padding: 16px;
    color: var(--error);
    font-size: 14px;
    margin-top: 16px;
}

/* ===== 响应式 ===== */
@media (max-width: 768px) {
    .navbar { padding: 0 16px; }
    .navbar-links a:not(.btn-nav) { display: none; }
    .hero h1 { font-size: 28px; }
    .hero p { font-size: 14px; }
    .steps { grid-template-columns: 1fr; gap: 24px; }
    .skills-grid { grid-template-columns: 1fr; }
    .features-grid { grid-template-columns: 1fr; }
    .form-row { grid-template-columns: 1fr; }
    .platforms-grid { grid-template-columns: repeat(2, 1fr); }
    .fab-cards { grid-template-columns: 1fr; }
    .tone-grid { grid-template-columns: repeat(2, 1fr); }
    .content-card { margin: 16px; padding: 20px; }
    .detail-hero h1 { font-size: 26px; }
}

@media (max-width: 480px) {
    .hero-buttons { flex-direction: column; align-items: center; }
    .platforms-grid { grid-template-columns: 1fr 1fr; }
}