/* iByter apihub landing 页样式 (M2 版本;后续 P5 可迁 less→Grunt) */

:root {
    --bg-0: #08101f;
    --bg-1: #0b1220;
    --bg-2: #101a2e;
    --border: rgba(255, 255, 255, 0.08);
    --text: #e6edf7;
    --text-dim: #a8b6d1;
    --text-mute: #64748b;
    --accent: #5b8cff;
    --accent-dim: rgba(91, 140, 255, 0.15);
    --gold: #ffb45c;
}

* { box-sizing: border-box; }
html, body { margin: 0; padding: 0; }
body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Microsoft YaHei", sans-serif;
    background: var(--bg-0);
    color: var(--text);
    line-height: 1.6;
    -webkit-font-smoothing: antialiased;
}
a { color: inherit; text-decoration: none; }
code { background: rgba(255, 255, 255, 0.08); padding: 2px 6px; border-radius: 4px; font-size: 0.9em; }

.section-inner { max-width: 1100px; margin: 0 auto; padding: 0 24px; }

/* ============ Nav ============ */
.apihub-nav {
    position: sticky;
    top: 0;
    z-index: 10;
    background: rgba(8, 16, 31, 0.85);
    backdrop-filter: blur(12px);
    border-bottom: 1px solid var(--border);
}
.nav-inner {
    max-width: 1100px;
    margin: 0 auto;
    padding: 16px 24px;
    display: flex;
    justify-content: space-between;
    align-items: center;
}
.brand {
    font-size: 20px;
    font-weight: 700;
    letter-spacing: 0.5px;
}
.brand span { color: var(--accent); font-weight: 500; }
.nav-links { display: flex; align-items: center; gap: 20px; }
.nav-links a { font-size: 14px; color: var(--text-dim); transition: color 0.15s; }
.nav-links a:hover { color: var(--text); }

.btn-outline, .btn-primary, .btn-primary-lg, .btn-ghost-lg, .btn-inline, .btn-block {
    display: inline-block; border-radius: 8px; transition: all 0.15s; cursor: pointer; border: 0; font-family: inherit;
}
.btn-outline {
    padding: 6px 14px; border: 1px solid var(--border); color: var(--text-dim); font-size: 14px;
}
.btn-outline:hover { border-color: var(--accent); color: var(--text); }
.btn-primary {
    padding: 6px 14px; background: var(--accent); color: #fff; font-size: 14px;
}
.btn-primary:hover { background: #6c9aff; }
.btn-primary-lg {
    padding: 14px 32px; background: var(--accent); color: #fff; font-size: 16px; font-weight: 600;
}
.btn-primary-lg:hover { background: #6c9aff; box-shadow: 0 8px 24px rgba(91, 140, 255, 0.3); }
.btn-ghost-lg {
    padding: 14px 32px; background: transparent; border: 1px solid var(--border); color: var(--text-dim); font-size: 16px;
}
.btn-ghost-lg:hover { border-color: var(--accent); color: var(--text); }
.btn-block { display: block; width: 100%; text-align: center; }
.btn-inline {
    padding: 10px 16px; background: var(--accent-dim); border: 1px solid var(--accent); color: var(--accent); font-size: 13px;
}
.btn-inline:hover { background: var(--accent); color: #fff; }
.btn-inline:disabled { opacity: 0.5; cursor: not-allowed; }

/* ============ Hero ============ */
.hero {
    padding: 80px 0 100px;
    background: radial-gradient(ellipse at top, rgba(91, 140, 255, 0.12), transparent 60%), var(--bg-0);
}
.hero-inner { max-width: 900px; margin: 0 auto; padding: 0 24px; text-align: center; }
.hero-eyebrow {
    display: inline-block;
    font-size: 13px;
    letter-spacing: 3px;
    color: var(--accent);
    text-transform: uppercase;
    padding: 6px 14px;
    border: 1px solid var(--accent-dim);
    border-radius: 999px;
    margin-bottom: 32px;
}
.hero-title {
    font-size: 56px;
    line-height: 1.15;
    font-weight: 700;
    margin: 0 0 24px;
    letter-spacing: -1px;
}
.hero-lead { font-size: 18px; color: var(--text-dim); margin: 0 0 40px; }
.hero-cta { display: flex; gap: 16px; justify-content: center; flex-wrap: wrap; }

/* ============ Features ============ */
.features { padding: 80px 0; background: var(--bg-1); border-top: 1px solid var(--border); border-bottom: 1px solid var(--border); }
.feature-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(240px, 1fr)); gap: 24px; }
.feature { text-align: center; padding: 24px; }
.feature-icon { font-size: 36px; margin-bottom: 12px; }
.feature h3 { font-size: 18px; margin: 0 0 8px; font-weight: 600; }
.feature p { color: var(--text-dim); margin: 0; font-size: 14px; }

/* ============ Pricing ============ */
.pricing, .billing, .cta { padding: 80px 0; }
.section-title { text-align: center; font-size: 36px; margin: 0 0 12px; letter-spacing: -0.5px; }
.section-lead { text-align: center; color: var(--text-dim); font-size: 16px; margin: 0 0 48px; }
.tier-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(180px, 1fr));
    gap: 20px;
    max-width: 1100px;
    margin: 0 auto;
}
.tier-card {
    position: relative;
    padding: 32px 20px 24px;
    background: var(--bg-2);
    border: 1px solid var(--border);
    border-radius: 14px;
    text-align: center;
    transition: transform 0.15s, border-color 0.15s;
}
.tier-card:hover { transform: translateY(-4px); border-color: var(--accent); }
.tier-card--recommended {
    border-color: var(--gold);
    box-shadow: 0 0 0 1px var(--gold);
}
.tier-badge {
    position: absolute;
    top: -12px; left: 50%;
    transform: translateX(-50%);
    background: var(--gold);
    color: #1a1300;
    font-size: 12px;
    font-weight: 700;
    padding: 4px 12px;
    border-radius: 999px;
    letter-spacing: 2px;
}
.tier-pay { font-size: 20px; color: var(--text-dim); margin-bottom: 4px; }
.tier-score { font-size: 32px; font-weight: 700; color: var(--text); margin-bottom: 8px; }
.tier-bonus { font-size: 13px; color: var(--gold); margin-bottom: 20px; min-height: 20px; }
.tier-bonus--zero { color: var(--text-mute); }
.tier-cta {
    display: block;
    padding: 10px;
    background: var(--accent-dim);
    color: var(--accent);
    border: 1px solid var(--accent);
    border-radius: 8px;
    font-size: 14px;
    font-weight: 600;
    transition: all 0.15s;
}
.tier-cta:hover { background: var(--accent); color: #fff; }

/* ============ Billing examples ============ */
.billing { background: var(--bg-1); border-top: 1px solid var(--border); border-bottom: 1px solid var(--border); }
.example-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(280px, 1fr)); gap: 20px; }
.example {
    background: var(--bg-2);
    border: 1px solid var(--border);
    border-radius: 12px;
    overflow: hidden;
}
.example-head { padding: 12px 20px; background: rgba(255,255,255,0.03); border-bottom: 1px solid var(--border); font-size: 14px; font-weight: 600; }
.example-body { padding: 20px; }
.example-body > div:first-child { color: var(--text-dim); font-size: 14px; margin-bottom: 12px; }
.example-cost { font-size: 24px; font-weight: 700; color: var(--accent); }
.example-cost span { font-size: 14px; color: var(--text-mute); margin-left: 8px; font-weight: 400; }

/* ============ CTA ============ */
.cta { background: linear-gradient(180deg, var(--bg-0), var(--bg-2)); text-align: center; }
.cta-inner h2 { font-size: 32px; margin: 0 0 32px; }
.cta-buttons { display: flex; gap: 16px; justify-content: center; flex-wrap: wrap; }

/* ============ Footer ============ */
.apihub-footer { padding: 32px 0; border-top: 1px solid var(--border); background: var(--bg-0); }
.footer-inner { display: flex; justify-content: space-between; align-items: center; color: var(--text-mute); font-size: 13px; flex-wrap: wrap; gap: 12px; }

/* ============ Auth pages ============ */
.auth-body { background: radial-gradient(ellipse at top, rgba(91, 140, 255, 0.08), transparent 50%), var(--bg-0); min-height: 100vh; }
.auth-wrap { min-height: 100vh; display: flex; flex-direction: column; align-items: center; justify-content: center; padding: 40px 20px; position: relative; }
.auth-back { position: absolute; top: 24px; left: 32px; color: var(--text-dim); font-size: 14px; }
.auth-back:hover { color: var(--text); }
.auth-card {
    width: 100%;
    max-width: 420px;
    background: var(--bg-2);
    border: 1px solid var(--border);
    border-radius: 16px;
    padding: 40px;
}
.brand-block { text-align: center; margin-bottom: 24px; }
.brand-block .brand { font-size: 24px; }
.auth-title { font-size: 28px; margin: 0 0 8px; text-align: center; }
.auth-lead { color: var(--text-dim); font-size: 14px; margin: 0 0 24px; text-align: center; }
.auth-form { display: flex; flex-direction: column; gap: 16px; }
.auth-form label { display: flex; flex-direction: column; gap: 6px; font-size: 13px; color: var(--text-dim); }
.auth-form label.row-with-btn { display: grid; grid-template-columns: 1fr auto; gap: 8px; }
.auth-form label.row-with-btn > span { grid-column: 1 / -1; }
.auth-form label.row-with-btn > input { grid-column: 1; }
.auth-form label.row-with-btn > .btn-inline { grid-column: 2; align-self: stretch; }
.auth-form input {
    padding: 12px 14px;
    background: var(--bg-1);
    border: 1px solid var(--border);
    border-radius: 8px;
    color: var(--text);
    font-size: 14px;
    font-family: inherit;
    outline: none;
    transition: border-color 0.15s;
}
.auth-form input:focus { border-color: var(--accent); }
.auth-alt { text-align: center; margin-top: 20px; font-size: 14px; color: var(--text-dim); }
.auth-alt a { color: var(--accent); }
.auth-alt a:hover { text-decoration: underline; }

/* ============ Responsive ============ */
@media (max-width: 640px) {
    .hero-title { font-size: 40px; }
    .section-title { font-size: 28px; }
    .auth-card { padding: 32px 24px; }
}