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

:root {
    --bg-deep: #F5F6FA;
    --bg-primary: #FFFFFF;
    --bg-card: #FFFFFF;
    --bg-elevated: #F8F9FD;
    --bg-hover: #F0F2F8;
    --border: rgba(0,0,0,0.06);
    --border-active: rgba(0,0,0,0.12);
    --text-primary: #0F172A;
    --text-secondary: #475569;
    --text-muted: #94A3B8;
    --accent: #4B7BFF;
    --accent-hover: #6391FF;
    --accent-subtle: rgba(75,123,255,0.10);
    --accent-cyan: #0CA678;
    --accent-amber: #D97706;
    --accent-rose: #E11D48;
    --accent-purple: #7C3AED;
    --font-sans: -apple-system, 'PingFang SC', 'Microsoft YaHei', 'Helvetica Neue', system-ui, sans-serif;
    --font-mono: 'Consolas', 'Courier New', monospace;
    --radius-sm: 8px;
    --radius-md: 14px;
    --radius-lg: 24px;
    --radius-xl: 32px;
    --shadow-card: 0 0 0 1px rgba(0,0,0,0.04), 0 4px 24px rgba(0,0,0,0.06);
    --shadow-glow: 0 0 60px rgba(75,123,255,0.08);
    --transition: 0.35s cubic-bezier(0.25, 0.1, 0.25, 1);
}

html { scroll-behavior: smooth; }

body {
    font-family: var(--font-sans);
    color: var(--text-secondary);
    background: var(--bg-primary);
    -webkit-font-smoothing: antialiased;
    line-height: 1.7;
    overflow-x: hidden;
}

a { color: inherit; text-decoration: none; }
img { max-width: 100%; display: block; }
button { cursor: pointer; font: inherit; }
::selection { background: var(--accent); color: #fff; }

.container { max-width: 1160px; margin: 0 auto; padding: 0 28px; }

.h1 { font-size: clamp(2rem, 4.5vw, 3.2rem); font-weight: 800; line-height: 1.12; letter-spacing: -0.03em; color: var(--text-primary); }
.h2 { font-size: clamp(1.5rem, 3vw, 2.2rem); font-weight: 700; line-height: 1.2; letter-spacing: -0.02em; color: var(--text-primary); }
.h3 { font-size: 1.1rem; font-weight: 600; line-height: 1.35; color: var(--text-primary); }
.body-lg { font-size: 1.05rem; line-height: 1.7; color: var(--text-secondary); }
.body { font-size: 0.9375rem; line-height: 1.7; color: var(--text-secondary); }

.section { padding: 80px 0; }
.section-header { text-align: center; margin-bottom: 48px; }
.section-header .body { max-width: 520px; margin: 12px auto 0; }
.section-label {
    display: inline-block;
    padding: 5px 14px;
    border-radius: 100px;
    font-size: 0.75rem; font-weight: 600;
    background: var(--accent-subtle);
    color: var(--accent);
    margin-bottom: 16px;
    letter-spacing: 0.02em;
}

.reveal { opacity: 0; transform: translateY(30px); transition: opacity 0.7s ease, transform 0.7s ease; }
.reveal.visible { opacity: 1; transform: translateY(0); }

/* Nav */
.nav {
    position: fixed; top: 0; left: 0; right: 0; z-index: 100;
    background: rgba(255,255,255,0.82);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    border-bottom: 1px solid var(--border);
    transition: var(--transition);
}
.nav.scrolled { background: rgba(255,255,255,0.95); }
.nav-inner {
    display: flex; align-items: center; justify-content: space-between;
    height: 64px;
}
.nav-logo {
    display: flex; align-items: center; gap: 10px;
    font-weight: 700; font-size: 1.1rem; color: var(--text-primary);
    letter-spacing: -0.01em;
}
.nav-logo-icon {
    width: 30px; height: 30px;
    background: var(--accent);
    border-radius: var(--radius-sm);
    display: flex; align-items: center; justify-content: center;
    color: #fff; font-size: 0.8rem;
    box-shadow: 0 0 20px var(--shadow-glow);
}
.nav-links { display: flex; align-items: center; gap: 32px; }
.nav-links a {
    font-size: 0.875rem; font-weight: 500; color: var(--text-secondary);
    transition: color 0.25s;
    position: relative;
}
.nav-links a::after {
    content: ''; position: absolute; bottom: -4px; left: 0; right: 0;
    height: 2px; background: var(--accent);
    transform: scaleX(0); transition: transform 0.3s;
}
.nav-links a:hover { color: var(--text-primary); }
.nav-links a:hover::after { transform: scaleX(1); }
.nav-links a.active { color: var(--accent); }
.nav-links a.active::after { transform: scaleX(1); }
.btn-nav {
    display: inline-flex; align-items: center; gap: 6px;
    padding: 8px 18px; border-radius: var(--radius-sm);
    font-size: 0.8125rem; font-weight: 600;
    background: var(--accent); color: #fff;
    transition: all 0.25s;
}
.btn-nav:hover { background: var(--accent-hover); box-shadow: 0 4px 16px rgba(75,123,255,0.25); }
.nav-toggle { display: none; background: none; border: none; font-size: 1.25rem; color: var(--text-secondary); }
.mobile-menu { max-height: 0; overflow: hidden; transition: max-height 0.4s; }
.mobile-menu.open { max-height: 400px; }
.mobile-menu a { display: block; padding: 12px 0; font-size: 0.9375rem; color: var(--text-secondary); border-bottom: 1px solid var(--border); }

@media (max-width: 768px) { .nav-links { display: none; } .nav-toggle { display: block; } }

/* Buttons */
.btn {
    display: inline-flex; align-items: center; gap: 8px;
    padding: 12px 24px; border-radius: var(--radius-sm);
    font-size: 0.875rem; font-weight: 600;
    transition: all 0.3s; border: none;
}
.btn-primary {
    background: var(--accent); color: #fff;
    box-shadow: 0 4px 16px rgba(75,123,255,0.20);
}
.btn-primary:hover { background: var(--accent-hover); transform: translateY(-2px); box-shadow: 0 8px 24px rgba(75,123,255,0.30); }
.btn-ghost {
    background: transparent;
    border: 1px solid var(--border-active);
    color: var(--text-primary);
}
.btn-ghost:hover { border-color: var(--accent); background: var(--accent-subtle); transform: translateY(-2px); }
.btn-sm { padding: 8px 18px; font-size: 0.8125rem; }

/* Hero */
.pricing-hero {
    padding: 120px 0 60px;
    position: relative;
    overflow: hidden;
    text-align: center;
}
.pricing-hero-bg {
    position: absolute; inset: 0;
    background-image:
        linear-gradient(rgba(0,0,0,0.04) 1px, transparent 1px),
        linear-gradient(90deg, rgba(0,0,0,0.04) 1px, transparent 1px);
    background-size: 64px 64px;
    mask-image: radial-gradient(ellipse 70% 50% at 50% 40%, #000, transparent);
    -webkit-mask-image: radial-gradient(ellipse 70% 50% at 50% 40%, #000, transparent);
}
.pricing-hero .hero-orb {
    position: absolute; border-radius: 50%; filter: blur(100px); pointer-events: none;
}
.pricing-hero .hero-orb-1 {
    width: 500px; height: 500px; background: rgba(75,123,255,0.06);
    top: -150px; right: -50px; animation: orb-drift 25s ease-in-out infinite;
}
.pricing-hero .hero-orb-2 {
    width: 350px; height: 350px; background: rgba(124,58,237,0.05);
    bottom: -100px; left: -80px; animation: orb-drift 30s ease-in-out infinite reverse;
}
@keyframes orb-drift {
    0%, 100% { transform: translate(0, 0); }
    33% { transform: translate(40px, -60px); }
    66% { transform: translate(-30px, 40px); }
}
.pricing-hero .h1 { margin-bottom: 16px; }
.pricing-hero .h1 .highlight {
    background: linear-gradient(135deg, var(--accent) 0%, #A78BFA 50%, var(--accent-cyan) 100%);
    -webkit-background-clip: text; -webkit-text-fill-color: transparent; background-clip: text;
}
.pricing-hero .body-lg { max-width: 560px; margin: 0 auto 40px; }
.pricing-hero-inner { position: relative; z-index: 1; }

/* Value Props */
.value-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 20px;
    margin-top: 48px;
}
.value-card {
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: var(--radius-md);
    padding: 28px;
    text-align: left;
    transition: var(--transition);
}
.value-card:hover { border-color: var(--border-active); box-shadow: var(--shadow-card); }
.value-card-icon {
    width: 40px; height: 40px; border-radius: 10px;
    display: flex; align-items: center; justify-content: center;
    font-size: 0.95rem; color: #fff;
    margin-bottom: 14px;
}
.value-card h3 { font-size: 1rem; margin-bottom: 6px; }
.value-card p { font-size: 0.85rem; color: var(--text-secondary); line-height: 1.65; }

@media (max-width: 768px) { .value-grid { grid-template-columns: 1fr; } }

/* Calculator */
.calc-wrap {
    max-width: 820px; margin: 0 auto;
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: var(--radius-md);
    padding: 40px;
}
.calc-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 36px;
}
.calc-label { font-size: 0.8125rem; font-weight: 600; color: var(--text-primary); margin-bottom: 8px; display: block; }
.calc-input-wrap { position: relative; }
.calc-input {
    width: 100%; padding: 10px 14px 10px 34px;
    border: 1px solid var(--border); border-radius: var(--radius-sm);
    font-size: 0.9375rem; font-family: var(--font-sans);
    background: var(--bg-primary); color: var(--text-primary);
    transition: border-color 0.2s;
    outline: none;
}
.calc-input:focus { border-color: var(--accent); box-shadow: 0 0 0 3px var(--accent-subtle); }
.calc-input-icon {
    position: absolute; left: 12px; top: 50%; transform: translateY(-50%);
    color: var(--text-muted); font-size: 0.8rem;
}
.calc-hint { font-size: 0.75rem; color: var(--text-muted); margin-top: 6px; }
.calc-result {
    background: var(--bg-elevated);
    border: 1px solid var(--border);
    border-radius: var(--radius-md);
    padding: 24px;
    display: flex; flex-direction: column; justify-content: center;
    height: 100%;
}
.calc-result-label { font-size: 0.85rem; color: var(--text-secondary); margin-bottom: 6px; text-align: center; }
.calc-result-value { font-size: 2rem; font-weight: 700; color: var(--accent); text-align: center; }
.calc-breakdown { margin-top: 16px; }
.calc-row {
    display: flex; justify-content: space-between;
    padding: 8px 0; font-size: 0.85rem;
    border-bottom: 1px solid var(--border);
}
.calc-row:last-child { border-bottom: none; font-weight: 600; color: var(--text-primary); }
.calc-note {
    margin-top: 16px; padding: 12px 14px;
    background: rgba(12,166,120,0.08); border-radius: var(--radius-sm);
    font-size: 0.8rem; color: var(--accent-cyan);
    display: flex; gap: 8px; align-items: flex-start;
}
.calc-note i { margin-top: 3px; }
.calc-footer { text-align: center; margin-top: 28px; }
.calc-footer p { font-size: 0.8rem; color: var(--accent); }

.calc-input::-webkit-outer-spin-button,
.calc-input::-webkit-inner-spin-button { -webkit-appearance: none; margin: 0; }
.calc-input[type=number] { -moz-appearance: textfield; }

@media (max-width: 768px) {
    .calc-wrap { padding: 24px; }
    .calc-grid { grid-template-columns: 1fr; gap: 24px; }
}

/* Plan Cards */
.plans-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 20px;
    align-items: start;
}
.plan-card {
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: var(--radius-md);
    overflow: hidden;
    transition: var(--transition);
    display: flex; flex-direction: column;
}
.plan-card:hover { border-color: var(--border-active); box-shadow: var(--shadow-card); transform: translateY(-4px); }
.plan-card.popular { border-color: var(--accent); box-shadow: 0 0 0 1px var(--accent), var(--shadow-card); }
.plan-card-header {
    padding: 20px 24px 16px;
    border-bottom: 1px solid var(--border);
}
.plan-card-header h3 { font-size: 0.9rem; }
.plan-card-header .tag {
    display: inline-block; padding: 2px 10px; border-radius: 100px;
    font-size: 0.7rem; font-weight: 600; margin-top: 6px;
}
.plan-card-header .tag.free { background: rgba(12,166,120,0.1); color: var(--accent-cyan); }
.plan-card-header .tag.paid { background: rgba(75,123,255,0.1); color: var(--accent); }
.plan-card-header .tag.custom { background: rgba(217,119,6,0.1); color: var(--accent-amber); }
.plan-price {
    padding: 16px 24px;
    border-bottom: 1px solid var(--border);
}
.plan-price .amount { font-size: 1.4rem; font-weight: 700; color: var(--text-primary); }
.plan-price .period { font-size: 0.8rem; color: var(--text-muted); }
.plan-price .original { font-size: 0.8rem; color: var(--text-muted); text-decoration: line-through; margin-left: 6px; }
.plan-body { padding: 16px 24px; flex: 1; }
.plan-body .sub { font-size: 0.8rem; font-weight: 600; color: var(--text-secondary); margin-bottom: 10px; }
.plan-body ul { list-style: none; display: flex; flex-direction: column; gap: 6px; }
.plan-body ul li {
    font-size: 0.8rem; color: var(--text-secondary);
    display: flex; align-items: flex-start; gap: 6px;
}
.plan-body ul li i { font-size: 0.4rem; color: var(--accent-cyan); margin-top: 6px; flex-shrink: 0; }
.plan-body ul li .highlight { color: var(--accent-amber); font-weight: 500; }
.plan-actions { padding: 16px 24px 24px; display: flex; flex-direction: column; gap: 8px; }
.plan-actions .btn { width: 100%; justify-content: center; }
.plan-actions .btn-sm { padding: 10px 18px; font-size: 0.8125rem; }

@media (max-width: 1024px) { .plans-grid { grid-template-columns: repeat(2, 1fr); } }
@media (max-width: 640px) { .plans-grid { grid-template-columns: 1fr; } }

/* Contact section */
.contact-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 16px;
    max-width: 520px;
    margin: 0 auto;
}
.contact-card {
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: var(--radius-md);
    padding: 24px;
    text-align: center;
    transition: var(--transition);
}
.contact-card:hover { border-color: var(--border-active); transform: translateY(-4px); box-shadow: var(--shadow-card); }
.contact-card-icon {
    width: 42px; height: 42px;
    border-radius: 12px;
    background: var(--accent-subtle);
    display: flex; align-items: center; justify-content: center;
    color: var(--accent); font-size: 1rem;
    margin: 0 auto 14px;
}
.contact-card h4 { font-size: 0.85rem; font-weight: 600; color: var(--text-primary); margin-bottom: 4px; }
.contact-card p { font-size: 0.8125rem; color: var(--text-secondary); }
.contact-card img { width: 130px; height: 130px; border-radius: var(--radius-sm); border: 1px solid var(--border); margin: 12px auto 0; }


@media (max-width: 480px) { .contact-grid { grid-template-columns: 1fr; } }

/* Footer */
.footer {
    background: #F0F2F6;
    border-top: 1px solid var(--border);
    padding: 60px 0 36px;
}
.footer-grid {
    display: grid;
    grid-template-columns: 2fr 1fr 1fr 1fr;
    gap: 40px;
}
.footer-brand { display: flex; align-items: center; gap: 10px; margin-bottom: 14px; }
.footer-brand-icon {
    width: 28px; height: 28px;
    background: var(--accent); border-radius: var(--radius-sm);
    display: flex; align-items: center; justify-content: center;
    color: #fff; font-size: 0.75rem;
    box-shadow: 0 0 16px rgba(75,123,255,0.15);
}
.footer-brand span { font-weight: 700; font-size: 1rem; color: var(--text-primary); }
.footer .desc { font-size: 0.8125rem; color: var(--text-secondary); max-width: 320px; line-height: 1.7; }
.footer .social { display: flex; gap: 14px; margin-top: 20px; }
.footer .social a {
    width: 36px; height: 36px;
    border-radius: 50%;
    border: 1px solid var(--border);
    display: flex; align-items: center; justify-content: center;
    font-size: 0.9rem; color: var(--text-secondary);
    transition: var(--transition);
}
.footer .social a:hover { border-color: var(--accent); color: var(--accent); background: var(--accent-subtle); }
.footer h4 {
    font-size: 0.75rem; font-weight: 600; text-transform: uppercase;
    letter-spacing: 0.08em; color: var(--text-primary);
    margin-bottom: 18px;
}
.footer-links { list-style: none; display: flex; flex-direction: column; gap: 12px; }
.footer-links a { font-size: 0.8125rem; color: var(--text-secondary); transition: color 0.25s; }
.footer-links a:hover { color: var(--text-secondary); }
.footer-bottom {
    border-top: 1px solid var(--border);
    margin-top: 44px; padding-top: 24px;
    text-align: center; font-size: 0.75rem; color: var(--text-secondary);
}
.footer-bottom a { color: inherit; }
.footer-bottom a:hover { color: var(--text-secondary); }

@media (max-width: 860px) { .footer-grid { grid-template-columns: 1fr 1fr; } }
@media (max-width: 480px) { .footer-grid { grid-template-columns: 1fr; } }

/* Modals */
.modal-overlay {
    position: fixed; inset: 0; z-index: 200;
    background: rgba(0,0,0,0.45);
    display: flex; align-items: center; justify-content: center;
    padding: 20px;
}
.modal-overlay.hidden { display: none; }
.modal-box {
    background: var(--bg-card);
    border-radius: var(--radius-lg);
    width: 100%; max-width: 500px;
    padding: 32px;
    box-shadow: 0 20px 60px rgba(0,0,0,0.15);
    max-height: 90vh; overflow-y: auto;
}
.modal-box.wide { max-width: 580px; }
.modal-header {
    display: flex; justify-content: space-between; align-items: center;
    margin-bottom: 20px;
}
.modal-header h3 { font-size: 1.1rem; font-weight: 600; color: var(--text-primary); }
.modal-close {
    background: none; border: none; font-size: 1.1rem;
    color: var(--text-muted); transition: color 0.2s;
}
.modal-close:hover { color: var(--text-primary); }
.modal-body { margin-bottom: 24px; }
.modal-body p { font-size: 0.875rem; color: var(--text-secondary); margin-bottom: 16px; }
.modal-actions { display: flex; justify-content: flex-end; gap: 8px; }

/* Form fields (modals) */
.form-group { margin-bottom: 16px; }
.form-label {
    display: block; font-size: 0.8125rem; font-weight: 500;
    color: var(--text-primary); margin-bottom: 6px;
}
.form-label .required { color: var(--accent-rose); }
.form-input {
    width: 100%; padding: 10px 14px;
    border: 1px solid var(--border); border-radius: var(--radius-sm);
    font-size: 0.875rem; font-family: var(--font-sans);
    background: var(--bg-primary); color: var(--text-primary);
    transition: border-color 0.2s; outline: none;
}
.form-input:focus { border-color: var(--accent); box-shadow: 0 0 0 3px var(--accent-subtle); }
.form-radio-group { display: flex; flex-direction: column; gap: 8px; }
.form-radio {
    display: flex; align-items: center; gap: 8px;
    font-size: 0.875rem; color: var(--text-secondary); cursor: pointer;
}
.form-radio input[type="radio"] { accent-color: var(--accent); }
.form-notice {
    padding: 10px 14px;
    background: rgba(245,158,11,0.08);
    border-radius: var(--radius-sm);
    font-size: 0.8rem; color: var(--accent-amber);
    display: flex; gap: 8px; align-items: flex-start;
    margin-top: 8px;
}
.form-notice i { margin-top: 3px; }

/* Key display */
.key-display {
    background: var(--bg-elevated);
    border: 1px solid var(--border);
    border-radius: var(--radius-sm);
    padding: 14px 16px;
    font-family: var(--font-mono);
    font-size: 0.9rem;
    color: var(--text-primary);
    word-break: break-all;
    position: relative;
}
.key-display-actions {
    display: flex; gap: 4px;
    position: absolute; top: -18px; right: 4px;
}
.key-display-actions button {
    background: var(--bg-card); border: 1px solid var(--border);
    border-radius: var(--radius-sm); padding: 4px 8px;
    font-size: 0.75rem; color: var(--text-muted); cursor: pointer;
    transition: all 0.2s;
}
.key-display-actions button:hover { border-color: var(--accent); color: var(--accent); }
.key-remark { font-size: 0.8125rem; font-weight: 600; color: var(--accent-rose); margin-top: 8px; }

/* Contact info in subscribe modal */
.contact-info { display: flex; flex-direction: column; gap: 12px; margin-bottom: 20px; }
.contact-info-item {
    display: flex; align-items: flex-start; gap: 10px;
}
.contact-info-icon {
    width: 30px; height: 30px; border-radius: 8px;
    display: flex; align-items: center; justify-content: center;
    font-size: 0.8rem; flex-shrink: 0;
}
.contact-info-item p { font-size: 0.8125rem; margin-bottom: 2px; }
.contact-info-item .label { color: var(--text-muted); font-size: 0.75rem; }
.contact-info-item .value { color: var(--text-primary); font-weight: 500; }
.modal-payment {
    padding: 12px 14px; border-radius: var(--radius-sm);
    font-size: 0.8125rem; margin-top: 8px;
}
.modal-payment.blue { background: rgba(75,123,255,0.06); color: var(--accent); }
.modal-payment.green { background: rgba(12,166,120,0.06); color: var(--accent-cyan); }
.modal-payment.amber { background: rgba(217,119,6,0.06); color: var(--accent-amber); }