:root {
    --blue: #1677ff;
    --blue-deep: #0e5ad6;
    --red: #d4202a;
    --red-deep: #9b1220;
    --gold: #e8c37a;
    --ink: #1c1412;
    --muted: #6f645e;
    --line: rgba(28, 20, 18, .08);
    --paper: #f6f1ea;
    --white: #fffdfb;
    --shadow: 0 18px 50px rgba(80, 18, 24, .12);
    --radius: 18px;
    --header-h: 64px;
    --max: 1120px;
}

* { box-sizing: border-box; -webkit-tap-highlight-color: transparent; }

html { scroll-behavior: smooth; }

html, body {
    margin: 0;
    min-height: 100%;
    font-family: "PingFang SC", "Hiragino Sans GB", "Noto Sans SC", "Microsoft YaHei", sans-serif;
    color: var(--ink);
    background: var(--paper);
}

body.nav-open { overflow: hidden; }

a { color: inherit; text-decoration: none; }
img { max-width: 100%; display: block; }
button, input { font: inherit; }

.wrap {
    width: min(100% - 32px, var(--max));
    margin: 0 auto;
}

.site-header {
    position: sticky;
    top: 0;
    z-index: 40;
    height: auto;
    min-height: var(--header-h);
    padding-top: env(safe-area-inset-top, 0px);
    background: rgba(255, 253, 251, .9);
    backdrop-filter: blur(16px);
    border-bottom: 1px solid var(--line);
}

.header-inner {
    height: var(--header-h);
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 16px;
}

.brand {
    display: flex;
    align-items: center;
    gap: 10px;
    min-width: 0;
}

.brand-logo {
    height: 44px;
    width: auto;
    display: block;
    flex-shrink: 0;
}

.brand-name {
    font-size: 15px;
    font-weight: 700;
    letter-spacing: .12em;
    white-space: nowrap;
}

.nav {
    display: none;
    align-items: center;
    gap: 4px;
}

.nav a {
    padding: 8px 12px;
    border-radius: 999px;
    font-size: 14px;
    color: var(--muted);
}

.nav a.is-active,
.nav a:hover { color: var(--ink); background: rgba(28, 20, 18, .05); }

.header-actions {
    display: flex;
    align-items: center;
    gap: 8px;
}

.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    height: 40px;
    padding: 0 16px;
    border-radius: 999px;
    border: 0;
    font-size: 14px;
    font-weight: 600;
    cursor: pointer;
    white-space: nowrap;
}

.btn-ghost {
    color: var(--muted);
    background: transparent;
}

.btn-primary {
    color: #fff;
    background: var(--blue);
    box-shadow: 0 8px 18px rgba(22, 119, 255, .28);
}

.btn-primary:hover { background: var(--blue-deep); }
.btn-ghost:hover { color: var(--ink); }

.nav-toggle {
    width: 40px;
    height: 40px;
    border: 0;
    border-radius: 12px;
    background: rgba(28, 20, 18, .05);
    display: inline-flex;
    flex-direction: column;
    justify-content: center;
    gap: 5px;
    padding: 0 11px;
    cursor: pointer;
}
.nav-toggle span {
    display: block;
    height: 2px;
    background: var(--ink);
    border-radius: 2px;
}

.drawer[hidden] { display: none !important; }
.drawer {
    position: fixed;
    inset: var(--header-h) 0 0;
    z-index: 39;
    background: rgba(28, 20, 18, .42);
}

body.nav-open .drawer { display: block; }

.drawer-panel {
    margin-left: auto;
    width: min(100%, 320px);
    height: 100%;
    background: var(--white);
    padding: 20px;
    display: flex;
    flex-direction: column;
    gap: 8px;
    box-shadow: -16px 0 40px rgba(0, 0, 0, .12);
}

.drawer a {
    padding: 14px 12px;
    border-radius: 12px;
    font-size: 16px;
}

.drawer a.is-active { background: #eef5ff; color: var(--blue); }

.hero {
    position: relative;
    overflow: hidden;
    color: #fff;
    background:
        radial-gradient(circle at 88% 12%, rgba(232, 195, 122, .35), transparent 28%),
        linear-gradient(160deg, #8b1024 0%, #c41e3a 42%, #165dff 100%);
}

.hero-inner {
    min-height: calc(100vh - var(--header-h));
    min-height: calc(100svh - var(--header-h));
    display: grid;
    align-items: center;
    gap: 36px;
    padding: 36px 0 48px;
}

.eyebrow {
    display: inline-flex;
    align-items: center;
    height: 28px;
    padding: 0 10px;
    border-radius: 999px;
    background: rgba(255,255,255,.16);
    border: 1px solid rgba(255,255,255,.22);
    font-size: 12px;
    letter-spacing: .16em;
}

.hero h1 {
    margin: 14px 0 12px;
    font-size: clamp(32px, 7vw, 56px);
    line-height: 1.12;
    letter-spacing: .08em;
}

.hero p {
    margin: 0 0 24px;
    max-width: 34em;
    font-size: 15px;
    line-height: 1.8;
    color: rgba(255,255,255,.88);
}

.hero-actions { display: flex; flex-wrap: wrap; gap: 10px; }

.btn-light {
    color: var(--red-deep);
    background: #fff;
}

.btn-on-hero {
    color: #fff;
    background: transparent;
    border: 1px solid rgba(255,255,255,.38);
}
.btn-on-hero:hover {
    background: rgba(255,255,255,.12);
    color: #fff;
}

#banner, #point, #scene, #flow, #usage {
    scroll-margin-top: calc(var(--header-h) + 10px);
}

.packet {
    width: min(100%, 280px);
    margin: 0 auto;
    aspect-ratio: 3 / 4;
    border-radius: 18px 18px 28px 28px;
    background: linear-gradient(180deg, #ff6a6f, #c41e3a 55%, #8b1024);
    box-shadow: 0 24px 50px rgba(0,0,0,.28);
    position: relative;
    display: grid;
    place-items: center;
}
.packet:before {
    content: "";
    position: absolute;
    top: -10px;
    left: 18px;
    right: 18px;
    height: 22px;
    background: var(--gold);
    border-radius: 10px 10px 3px 3px;
}
.packet-fu {
    font-size: 92px;
    font-weight: 700;
    color: var(--gold);
    line-height: 1;
    text-shadow: 0 8px 0 rgba(139, 16, 36, .25);
}
.packet-sub {
    position: absolute;
    bottom: 28px;
    color: rgba(255,255,255,.85);
    letter-spacing: .3em;
    font-size: 13px;
}

.section {
    padding: 72px 0;
}

.section.alt { background: #efe8df; }

.section-head { text-align: center; margin-bottom: 36px; }

.section-head h2 {
    margin: 0;
    font-size: clamp(24px, 4vw, 34px);
    letter-spacing: .12em;
}

.section-head p {
    margin: 8px 0 0;
    color: var(--muted);
    letter-spacing: .2em;
    font-size: 12px;
    text-transform: uppercase;
}

.feature-grid {
    display: grid;
    grid-template-columns: 1fr;
    gap: 14px;
}

.feature {
    background: var(--white);
    border-radius: var(--radius);
    padding: 22px 20px;
    box-shadow: var(--shadow);
}

.feature-icon {
    width: 48px;
    height: 48px;
    border-radius: 14px;
    display: grid;
    place-items: center;
    margin-bottom: 14px;
    background: #fff1f0;
}

.feature-icon img { width: 28px; height: 28px; }

.feature h3 {
    margin: 0 0 8px;
    font-size: 16px;
    line-height: 1.5;
}

.feature p {
    margin: 0;
    color: var(--muted);
    font-size: 13px;
    line-height: 1.7;
}

.help-banner {
    margin-top: 28px;
    border-radius: 22px;
    padding: 22px;
    display: grid;
    gap: 16px;
    color: #fff;
    background: linear-gradient(120deg, var(--red) 0%, #1677ff 100%);
    box-shadow: var(--shadow);
}

.help-banner p {
    margin: 0;
    font-size: 16px;
    line-height: 1.6;
}

.help-banner .btn-light { width: fit-content; }

.scene-grid,
.usage-grid {
    display: grid;
    grid-template-columns: 1fr;
    gap: 14px;
}

.scene-card, .usage-card {
    background: var(--white);
    border-radius: var(--radius);
    padding: 22px;
    box-shadow: var(--shadow);
}

.scene-card h3, .usage-card h3 { margin: 0 0 8px; font-size: 18px; }
.scene-card p, .usage-card p { margin: 0; color: var(--muted); line-height: 1.7; font-size: 14px; }

.usage-qr {
    width: min(100%, 200px);
    height: auto;
    margin: 16px auto 0;
    border-radius: 12px;
    background: #fff;
}

.scene-no {
    display: inline-block;
    margin-bottom: 10px;
    color: var(--blue);
    font-weight: 700;
    letter-spacing: .12em;
    font-size: 12px;
}

.steps {
    display: grid;
    gap: 12px;
}

.step {
    background: var(--white);
    border-radius: var(--radius);
    padding: 18px 18px 18px 20px;
    box-shadow: var(--shadow);
    display: grid;
    grid-template-columns: 42px 1fr;
    gap: 12px;
    align-items: start;
}

.step-num {
    width: 42px;
    height: 42px;
    border-radius: 50%;
    background: #eef5ff;
    color: var(--blue);
    display: grid;
    place-items: center;
    font-weight: 700;
}

.step h3 { margin: 4px 0 6px; font-size: 16px; }
.step p { margin: 0; color: var(--muted); font-size: 13px; line-height: 1.6; }

.page-hero {
    padding: 48px 0 28px;
    background: linear-gradient(160deg, #8b1024 0%, #c41e3a 50%, #1677ff 100%);
    color: #fff;
}

.page-hero h1 {
    margin: 0 0 10px;
    font-size: clamp(28px, 6vw, 42px);
    letter-spacing: .1em;
}

.page-hero p {
    margin: 0;
    max-width: 28em;
    line-height: 1.7;
    color: rgba(255,255,255,.88);
}

.form-card {
    background: var(--white);
    border-radius: 24px;
    padding: 24px 18px 28px;
    box-shadow: var(--shadow);
    margin-top: -28px;
    margin-bottom: 48px;
}

.field { margin-bottom: 18px; }

.field label {
    display: block;
    margin-bottom: 8px;
    font-size: 14px;
    font-weight: 600;
}

.field input {
    width: 100%;
    height: 48px;
    border: 1px solid #eadfd6;
    border-radius: 14px;
    padding: 0 14px;
    background: #fff;
    outline: none;
    font-size: 16px;
}

.field input:focus { border-color: var(--blue); box-shadow: 0 0 0 3px rgba(22,119,255,.12); }

.amount-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 8px;
}

.amount-item {
    height: 44px;
    border-radius: 12px;
    border: 1px solid #eadfd6;
    display: grid;
    place-items: center;
    color: var(--muted);
    cursor: pointer;
    font-size: 14px;
}

.amount-item.is-active {
    color: var(--blue);
    border-color: var(--blue);
    background: #eef5ff;
    font-weight: 600;
}

.form-submit {
    width: 100%;
    height: 50px;
    margin-top: 10px;
}

.form-submit:disabled { opacity: .6; }

.site-footer {
    background: #17131f;
    color: rgba(255,255,255,.78);
    padding: 40px 0 calc(24px + env(safe-area-inset-bottom, 0px));
}

.footer-top {
    display: grid;
    gap: 24px;
}

.footer-brand {
    font-size: 20px;
    font-weight: 700;
    color: #fff;
    letter-spacing: .12em;
    display: flex;
    align-items: center;
    gap: 12px;
}
.footer-logo {
    height: 52px;
    width: auto;
    display: block;
}

.footer-links {
    display: flex;
    flex-wrap: wrap;
    gap: 10px 16px;
}

.footer-links a { color: rgba(255,255,255,.78); font-size: 14px; }
.footer-links a:hover { color: #fff; }

.footer-info p { margin: 0 0 8px; font-size: 13px; line-height: 1.6; }

.footer-bottom {
    margin-top: 24px;
    padding-top: 16px;
    border-top: 1px solid rgba(255,255,255,.1);
    display: grid;
    gap: 8px;
    font-size: 12px;
}

.footer-bottom a { color: rgba(255,255,255,.7); }

.toast {
    position: fixed;
    left: 50%;
    top: 18%;
    transform: translate(-50%, -20px);
    opacity: 0;
    pointer-events: none;
    background: rgba(28, 20, 18, .92);
    color: #fff;
    padding: 12px 18px;
    border-radius: 12px;
    font-size: 14px;
    max-width: 80%;
    text-align: center;
    z-index: 60;
    transition: .2s ease;
}
.toast.show { opacity: 1; transform: translate(-50%, 0); }

@media (min-width: 768px) {
    :root { --header-h: 72px; }
    .nav-toggle { display: none; }
    .nav { display: flex; }
    .brand-logo { height: 52px; }
    .brand-name { font-size: 16px; }
    .hero-inner {
        grid-template-columns: 1.1fr .9fr;
        padding: 56px 0;
        min-height: 640px;
    }
    .feature-grid { grid-template-columns: repeat(2, 1fr); }
    .scene-grid { grid-template-columns: repeat(2, 1fr); }
    .usage-grid { grid-template-columns: repeat(2, 1fr); }
    .steps { grid-template-columns: repeat(2, 1fr); }
    .form-card { padding: 36px 40px 40px; }
    .form-submit { width: 220px; }
    .footer-top { grid-template-columns: 1fr 1.4fr; }
    .footer-bottom { grid-template-columns: 1fr auto; align-items: center; }
}

@media (min-width: 1024px) {
    .feature-grid { grid-template-columns: repeat(6, 1fr); }
    .feature { grid-column: span 2; }
    .feature:nth-child(4) { grid-column: 2 / span 2; }
    .feature:nth-child(5) { grid-column: 4 / span 2; }
    .scene-grid { grid-template-columns: repeat(3, 1fr); }
    .usage-grid { grid-template-columns: repeat(4, 1fr); }
    .steps { grid-template-columns: repeat(5, 1fr); }
    .help-banner {
        grid-template-columns: 1fr auto;
        align-items: center;
        padding: 28px 32px;
    }
}

@media (max-width: 380px) {
    .brand-name { display: none; }
}