/* ==================== CSS VARIABLES ==================== */
:root {
    --primary: #1a6fb5; --primary-dark: #145d96; --primary-light: #e8f4fd;
    --primary-lighter: #f4f9fd; --accent: #0ea5e9; --success: #10b981;
    --warning: #f59e0b; --danger: #ef4444; --text: #1e293b;
    --text-light: #64748b; --text-lighter: #94a3b8; --bg: #ffffff;
    --bg-alt: #f8fafc; --border: #e2e8f0;
    --shadow-lg: 0 20px 25px -5px rgba(0,0,0,0.1), 0 8px 10px -6px rgba(0,0,0,0.04);
    --radius: 12px; --radius-lg: 20px; --transition: 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

/* ==================== RESET ==================== */
* { margin: 0; padding: 0; box-sizing: border-box; }
html { scroll-behavior: smooth; scroll-padding-top: 80px; }
body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'PingFang SC', 'Hiragino Sans GB', 'Microsoft YaHei', sans-serif;
    color: var(--text); background: var(--bg); line-height: 1.7;
}

/* ==================== NAVIGATION ==================== */
.nav {
    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); transition: var(--transition);
}
.nav.scrolled { box-shadow: 0 4px 20px rgba(0,0,0,0.08); }
.nav-inner {
    max-width: 1200px; margin: 0 auto; padding: 0 24px;
    display: flex; align-items: center; justify-content: space-between; height: 72px;
}
.nav-logo {
    display: flex; align-items: center; gap: 12px; text-decoration: none; color: var(--primary);
}
.nav-logo-text { font-size: 22px; font-weight: 700; letter-spacing: 2px; }
.nav-links { display: flex; align-items: center; gap: 4px; list-style: none; }
.nav-links a {
    text-decoration: none; color: var(--text-light); font-size: 15px; font-weight: 500;
    padding: 8px 18px; border-radius: 8px; transition: var(--transition);
}
.nav-links a:hover, .nav-links a.active { color: var(--primary); background: var(--primary-lighter); }
.nav-cta { background: var(--primary) !important; color: #fff !important; padding: 10px 24px !important; font-weight: 600 !important; }
.nav-cta:hover { background: var(--primary-dark) !important; }
.nav-toggle { display: none; background: none; border: none; cursor: pointer; padding: 8px; }
.nav-toggle span { display: block; width: 26px; height: 2.5px; background: var(--text); border-radius: 2px; margin: 5px 0; transition: var(--transition); }

@media (max-width: 900px) {
    .nav-links {
        position: fixed; top: 72px; left: 0; right: 0;
        background: rgba(255,255,255,0.98); backdrop-filter: blur(20px);
        flex-direction: column; padding: 16px; gap: 4px;
        border-bottom: 1px solid var(--border); box-shadow: 0 20px 30px rgba(0,0,0,0.1);
        transform: translateY(-120%); opacity: 0; pointer-events: none; transition: var(--transition);
    }
    .nav-links.open { transform: translateY(0); opacity: 1; pointer-events: all; }
    .nav-links a { display: block; padding: 14px 18px; font-size: 16px; }
    .nav-toggle { display: block; }
}

/* ==================== PAGE BANNER ==================== */
.page-banner {
    padding: 140px 24px 60px;
    background: linear-gradient(160deg, #e8f4fd 0%, #d4e7f7 35%, #c8e0f3 65%, #e0f0fa 100%);
    position: relative; overflow: hidden;
}
.page-banner::before {
    content: ''; position: absolute; inset: 0; opacity: 0.1;
    background-image: radial-gradient(circle, var(--primary) 1px, transparent 1px);
    background-size: 30px 30px;
}
.page-banner-inner {
    max-width: 1200px; margin: 0 auto; position: relative; z-index: 1; text-align: center;
}
.page-banner h1 { font-size: 40px; font-weight: 800; margin-bottom: 12px; }
.page-banner h1 span { background: linear-gradient(135deg, var(--primary), var(--accent)); -webkit-background-clip: text; -webkit-text-fill-color: transparent; background-clip: text; }
.page-banner p { font-size: 17px; color: var(--text-light); max-width: 500px; margin: 0 auto; }
.breadcrumb { margin-top: 20px; font-size: 14px; color: var(--text-lighter); }
.breadcrumb a { color: var(--primary); text-decoration: none; }
.breadcrumb a:hover { text-decoration: underline; }

/* ==================== SECTIONS ==================== */
.section { padding: 60px 24px; }
.section-alt { background: var(--bg-alt); }
.container { max-width: 1200px; margin: 0 auto; }
.section-header { text-align: center; margin-bottom: 60px; }
.section-tag { display: inline-block; background: var(--primary-lighter); color: var(--primary); font-size: 13px; font-weight: 600; padding: 6px 18px; border-radius: 20px; margin-bottom: 16px; letter-spacing: 1.5px; }
.section-title { font-size: 36px; font-weight: 700; margin-bottom: 12px; letter-spacing: -0.5px; }
.section-subtitle { font-size: 17px; color: var(--text-light); max-width: 600px; margin: 0 auto; }

/* ==================== FILTER TABS ==================== */
.filter-section { padding: 40px 24px 0; background: var(--bg); }
.filter-inner { max-width: 1200px; margin: 0 auto; }
.filter-tabs {
    display: flex; gap: 8px; flex-wrap: wrap; justify-content: center;
    border-bottom: 2px solid var(--border); padding-bottom: 0;
}
.filter-tab {
    padding: 12px 28px; font-size: 15px; font-weight: 600; color: var(--text-light);
    background: none; border: none; cursor: pointer; border-radius: 8px 8px 0 0;
    transition: var(--transition); position: relative; font-family: inherit;
}
.filter-tab::after {
    content: ''; position: absolute; bottom: -2px; left: 0; right: 0; height: 3px;
    background: var(--primary); border-radius: 3px 3px 0 0; opacity: 0; transition: var(--transition);
}
.filter-tab:hover { color: var(--primary); }
.filter-tab.active { color: var(--primary); background: var(--primary-lighter); }
.filter-tab.active::after { opacity: 1; }

/* ==================== BUTTONS ==================== */
.btn {
    display: inline-flex; align-items: center; gap: 8px; padding: 14px 32px;
    border-radius: 12px; font-size: 16px; font-weight: 600; text-decoration: none;
    transition: var(--transition); cursor: pointer; border: none; font-family: inherit;
}
.btn-primary { background: var(--primary); color: #fff; box-shadow: 0 4px 16px rgba(26,111,181,0.3); }
.btn-primary:hover { background: var(--primary-dark); transform: translateY(-2px); box-shadow: 0 8px 24px rgba(26,111,181,0.35); }
.btn-outline { background: #fff; color: var(--primary); border: 2px solid var(--primary); }
.btn-outline:hover { background: var(--primary-lighter); transform: translateY(-2px); }

/* ==================== FORM ==================== */
.form-group { margin-bottom: 18px; }
.form-group label { display: block; font-size: 14px; font-weight: 600; margin-bottom: 6px; }
.form-group input, .form-group select, .form-group textarea {
    width: 100%; padding: 12px 16px; border: 1.5px solid var(--border); border-radius: 10px;
    font-size: 15px; color: var(--text); background: var(--bg); transition: var(--transition); outline: none; font-family: inherit;
    box-sizing: border-box; height: 48px;
}
.form-group textarea { height: auto; min-height: 100px; resize: vertical; }
.form-group input[type="date"] { padding: 11px 16px; -webkit-appearance: none; appearance: none; }
.form-group select {
    -webkit-appearance: none;
    -moz-appearance: none;
    appearance: none;
    background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='16' height='16' viewBox='0 0 24 24' fill='none' stroke='%2364748b' stroke-width='2' stroke-linecap='round' stroke-linejoin='round'%3E%3Cpolyline points='6 9 12 15 18 9'%3E%3C/polyline%3E%3C/svg%3E");
    background-repeat: no-repeat;
    background-position: right 12px center;
    background-size: 16px;
    padding-right: 40px;
    cursor: pointer;
}
.form-group select::-ms-expand { display: none; }
.form-group input:focus, .form-group select:focus, .form-group textarea:focus {
    border-color: var(--primary); box-shadow: 0 0 0 3px rgba(26,111,181,0.1);
}
.form-group textarea { resize: vertical; min-height: 100px; }
.form-row { display: grid; grid-template-columns: 1fr 1fr; gap: 16px; }
.form-submit {
    width: 100%; padding: 14px; background: var(--primary); color: #fff; border: none;
    border-radius: 10px; font-size: 16px; font-weight: 600; cursor: pointer; transition: var(--transition); font-family: inherit; margin-top: 8px;
}
.form-submit:hover { background: var(--primary-dark); transform: translateY(-1px); }

/* ==================== FOOTER ==================== */
.footer { background: #0f172a; color: #cbd5e1; padding: 64px 24px 32px; }
.footer-grid { max-width: 1200px; margin: 0 auto 40px; display: grid; grid-template-columns: 2fr 1fr 1fr 1fr; gap: 40px; }
.footer-brand h3 { color: #fff; font-size: 20px; font-weight: 700; margin-bottom: 12px; }
.footer-brand p { font-size: 14px; line-height: 1.8; opacity: 0.7; }
.footer-col h4 {
    color: #fff; font-size: 15px; font-weight: 600; margin-bottom: 18px;
    padding-left: 14px; position: relative;
}
.footer-col h4::before {
    content: ''; position: absolute; left: 0; top: 2px; bottom: 2px; width: 3px;
    background: var(--primary); border-radius: 2px;
}
.footer-col ul { list-style: none; }
.footer-col ul li { margin-bottom: 10px; }
.footer-col ul li a {
    color: #94a3b8; text-decoration: none; font-size: 14px;
    transition: var(--transition); display: inline-block; padding-left: 0;
}
.footer-col ul li a:hover { color: #fff; padding-left: 8px; }
.footer-bottom {
    max-width: 1200px; margin: 0 auto; padding-top: 24px;
    border-top: 1px solid rgba(255,255,255,0.08);
    display: flex; justify-content: space-between; align-items: center;
    font-size: 13px; opacity: 0.5;
}
@media (max-width: 1024px) { .footer-grid { grid-template-columns: 1fr 1fr 1fr; }
    .footer-brand { grid-column: 1 / -1; }
}
@media (max-width: 768px) { .footer-grid { grid-template-columns: 1fr 1fr; } }
@media (max-width: 480px) { .footer-grid { grid-template-columns: 1fr; } .footer-bottom { flex-direction: column; gap: 8px; text-align: center; } }

/* ==================== BACK TO TOP ==================== */
.back-to-top {
    position: fixed; bottom: 30px; right: 30px; width: 48px; height: 48px;
    background: var(--primary); color: #fff; border: none; border-radius: 14px;
    cursor: pointer; z-index: 999; box-shadow: 0 4px 16px rgba(26,111,181,0.3);
    transition: var(--transition); opacity: 0; pointer-events: none;
    display: flex; align-items: center; justify-content: center; font-size: 22px; font-weight: bold;
}
.back-to-top.visible { opacity: 1; pointer-events: all; }
.back-to-top:hover { transform: translateY(-3px); box-shadow: 0 8px 24px rgba(26,111,181,0.4); }

/* ==================== SCROLL REVEAL ==================== */
.reveal { opacity: 0; transform: translateY(40px); transition: opacity 0.7s ease, transform 0.7s ease; }
.reveal.visible { opacity: 1; transform: translateY(0); }
.d1 { transition-delay: 0.1s; } .d2 { transition-delay: 0.2s; } .d3 { transition-delay: 0.3s; } .d4 { transition-delay: 0.4s; }

/* ==================== TOAST ==================== */
.toast {
    position: fixed; bottom: 30px; left: 50%;
    transform: translateX(-50%) translateY(100px);
    background: var(--success); color: #fff; padding: 14px 28px; border-radius: 10px;
    font-weight: 600; font-size: 15px; z-index: 9999;
    transition: transform 0.4s cubic-bezier(0.175, 0.885, 0.32, 1.275);
    box-shadow: 0 10px 30px rgba(16, 185, 129, 0.3);
}
.toast.show { transform: translateX(-50%) translateY(0); }
.toast.error { background: var(--danger); box-shadow: 0 10px 30px rgba(239,68,68,0.3); }

/* ==================== MODAL ==================== */
.modal-overlay {
    position: fixed; inset: 0; background: rgba(0,0,0,0.5); z-index: 10000;
    display: flex; align-items: center; justify-content: center;
    opacity: 0; pointer-events: none; transition: opacity 0.3s;
}
.modal-overlay.show { opacity: 1; pointer-events: all; }
.modal {
    background: #fff; border-radius: var(--radius-lg); padding: 40px;
    text-align: center; max-width: 420px; width: 90%; box-shadow: var(--shadow-lg);
}
.modal-icon { width: 72px; height: 72px; background: #d1fae5; border-radius: 50%; display: flex; align-items: center; justify-content: center; margin: 0 auto 20px; font-size: 36px; }
.modal h3 { font-size: 22px; font-weight: 700; margin-bottom: 8px; }
.modal p { color: var(--text-light); font-size: 15px; margin-bottom: 24px; }
.modal-btn { padding: 12px 36px; background: var(--primary); color: #fff; border: none; border-radius: 10px; font-size: 15px; font-weight: 600; cursor: pointer; font-family: inherit; transition: var(--transition); }
.modal-btn:hover { background: var(--primary-dark); }

@media (max-width: 900px) {
    .form-row { grid-template-columns: 1fr; }
}