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

:root{
    --bg:#f5f8f7;
    --paper:#ffffff;
    --card:#ffffff;
    --text:#17211f;
    --muted:#66726f;
    --line:rgba(23,33,31,0.12);
    --accent:#18a999;
    --accent-dark:#0b7f75;
    --accent-soft:#e8f8f5;
    --blue:#2f7cff;
    --dark:#101817;
    --dark-card:#17211f;
    --shadow:0 22px 60px rgba(23,33,31,0.10);
}

html{
    scroll-behavior:smooth;
}

body{
    font-family:Arial, Helvetica, sans-serif;
    background:var(--bg);
    color:var(--text);
    line-height:1.6;
}

button,
input,
textarea,
select{
    font:inherit;
}

a{
    color:inherit;
    text-decoration:none;
}

.container{
    width:min(1120px, calc(100% - 40px));
    margin:0 auto;
}

.guide-header{
    position:sticky;
    top:0;
    z-index:50;
    background:rgba(245,248,247,0.92);
    backdrop-filter:blur(18px);
    border-bottom:1px solid var(--line);
}

.guide-header-inner{
    width:min(1180px, calc(100% - 40px));
    min-height:74px;
    margin:0 auto;
    display:flex;
    align-items:center;
    justify-content:space-between;
    gap:24px;
}

.back-link{
    display:inline-flex;
    align-items:center;
    min-height:42px;
    padding:0 16px;
    border-radius:999px;
    background:#fff;
    border:1px solid var(--line);
    font-weight:700;
}

.quick-nav{
    display:flex;
    align-items:center;
    gap:22px;
    color:#60706d;
    font-size:15px;
    white-space:nowrap;
}

.quick-nav a{
    padding:8px 0;
    transition:color .2s ease;
}

.quick-nav a:hover{
    color:var(--accent-dark);
}

.hero{
    padding:92px 0 78px;
    background:
        radial-gradient(circle at 12% 18%, rgba(24,169,153,0.16), transparent 30%),
        radial-gradient(circle at 86% 18%, rgba(47,124,255,0.12), transparent 28%),
        linear-gradient(135deg, #f9fbf8, #e8f3f1);
    border-bottom:1px solid var(--line);
}

.hero-grid{
    display:grid;
    grid-template-columns:minmax(0, 1.15fr) minmax(320px, 0.85fr);
    gap:44px;
    align-items:center;
}

.eyebrow,
.section-kicker{
    color:var(--accent-dark);
    font-size:17px;
    font-weight:700;
    margin-bottom:14px;
}

.hero-copy h1{
    max-width:720px;
    font-size:clamp(48px, 8vw, 86px);
    line-height:1;
    margin-bottom:24px;
}

.hero-copy p{
    max-width:700px;
    color:var(--muted);
    font-size:18px;
}

.hero-actions{
    display:flex;
    flex-wrap:wrap;
    gap:14px;
    margin-top:30px;
}

.btn{
    display:inline-flex;
    align-items:center;
    justify-content:center;
    min-height:48px;
    padding:0 22px;
    border-radius:999px;
    font-weight:700;
    transition:transform .2s ease, box-shadow .2s ease, background .2s ease;
}

.btn:hover{
    transform:translateY(-2px);
}

.btn-primary{
    background:var(--dark);
    color:#fff;
    box-shadow:0 16px 34px rgba(16,24,23,0.18);
}

.btn-secondary{
    background:rgba(255,255,255,0.78);
    border:1px solid var(--line);
}

.spec-panel{
    background:rgba(255,255,255,0.86);
    border:1px solid rgba(255,255,255,0.72);
    border-radius:30px;
    padding:30px;
    box-shadow:var(--shadow);
}

.spec-panel h2{
    font-size:24px;
    margin-bottom:18px;
}

.spec-panel ul{
    display:grid;
    gap:12px;
    list-style:none;
    color:#4d5a57;
}

.spec-panel strong{
    color:var(--text);
}

.section{
    padding:82px 0;
}

.section-head{
    text-align:center;
    margin-bottom:34px;
}

.section-head h2,
.section-intro h2,
.video-copy h2,
.support-box h2{
    font-size:clamp(30px, 4vw, 46px);
    line-height:1.1;
    margin-bottom:12px;
}

.section-head p,
.section-intro p,
.video-copy p,
.support-box p{
    color:var(--muted);
}

.section-head p{
    max-width:720px;
    margin:0 auto;
}

.step-grid{
    display:grid;
    grid-template-columns:repeat(4, minmax(0, 1fr));
    gap:18px;
}

.step-card{
    background:var(--card);
    border:1px solid var(--line);
    border-radius:26px;
    padding:24px;
    box-shadow:0 16px 44px rgba(23,33,31,0.06);
}

.step-card span,
.ai-steps span{
    display:inline-flex;
    width:42px;
    height:42px;
    align-items:center;
    justify-content:center;
    border-radius:16px;
    background:var(--accent-soft);
    color:var(--accent-dark);
    font-weight:700;
    margin-bottom:18px;
}

.step-card h3,
.use-card h3,
.video-card h3,
.notice-card h3,
.ai-steps h3{
    font-size:22px;
    line-height:1.18;
    margin-bottom:10px;
}

.step-card p,
.use-card p,
.video-card p,
.notice-card p,
.ai-steps p{
    color:var(--muted);
}

.video-section{
    background:#fff;
    border-top:1px solid var(--line);
    border-bottom:1px solid var(--line);
}

.video-layout{
    display:grid;
    grid-template-columns:minmax(260px, 0.85fr) minmax(0, 1.15fr);
    gap:32px;
    align-items:center;
}

.video-card{
    background:linear-gradient(135deg, #10201d, #183d38);
    color:#fff;
    border-radius:30px;
    padding:32px;
    min-height:230px;
    display:flex;
    flex-direction:column;
    justify-content:space-between;
    box-shadow:var(--shadow);
}

.video-card p{
    color:rgba(255,255,255,0.76);
}

.video-card a{
    display:inline-flex;
    align-self:flex-start;
    margin-top:24px;
    padding:12px 18px;
    border-radius:999px;
    background:var(--accent);
    color:#fff;
    font-weight:700;
}

.dark-section{
    background:var(--dark);
    color:#fff;
}

.dark-section .section-kicker{
    color:#8ee7dc;
}

.split-layout{
    display:grid;
    grid-template-columns:minmax(260px, 0.82fr) minmax(0, 1.18fr);
    gap:42px;
    align-items:start;
}

.dark-section .section-intro p{
    color:rgba(255,255,255,0.68);
}

.notice-list{
    display:grid;
    gap:14px;
}

.notice-card{
    padding:22px;
    border-radius:24px;
    background:rgba(255,255,255,0.08);
    border:1px solid rgba(255,255,255,0.12);
}

.notice-card p{
    color:rgba(255,255,255,0.68);
}

.use-grid{
    display:grid;
    grid-template-columns:repeat(3, minmax(0, 1fr));
    gap:20px;
}

.use-card{
    background:#fff;
    border:1px solid var(--line);
    border-radius:26px;
    padding:26px;
}

.soft-section{
    background:#eef9f7;
    border-top:1px solid var(--line);
    border-bottom:1px solid var(--line);
}

.ai-layout{
    display:grid;
    grid-template-columns:minmax(260px, 0.8fr) minmax(0, 1.2fr);
    gap:42px;
    align-items:start;
}

.ai-steps{
    display:grid;
    grid-template-columns:repeat(2, minmax(0, 1fr));
    gap:18px;
}

.ai-steps article{
    background:#fff;
    border:1px solid rgba(23,33,31,0.10);
    border-radius:26px;
    padding:24px;
    box-shadow:0 14px 42px rgba(23,33,31,0.05);
}

.faq-list{
    display:grid;
    gap:14px;
    max-width:920px;
}

.faq-list details{
    background:#fff;
    border:1px solid var(--line);
    border-radius:22px;
    padding:0 22px;
    box-shadow:0 12px 36px rgba(23,33,31,0.05);
}

.faq-list summary{
    cursor:pointer;
    list-style:none;
    padding:20px 0;
    font-size:18px;
    font-weight:700;
    display:flex;
    align-items:center;
    justify-content:space-between;
    gap:18px;
}

.faq-list summary::-webkit-details-marker{
    display:none;
}

.faq-list summary::after{
    content:"+";
    width:32px;
    height:32px;
    display:grid;
    place-items:center;
    border-radius:999px;
    background:var(--accent-soft);
    color:var(--accent-dark);
    flex:0 0 auto;
}

.faq-list details[open] summary::after{
    content:"−";
}

.faq-list p{
    color:var(--muted);
    padding:0 0 22px;
}

.support-section{
    background:#fff;
}

.support-box{
    display:grid;
    grid-template-columns:minmax(260px, 0.85fr) minmax(0, 1.15fr);
    gap:40px;
    align-items:start;
    padding:38px;
    border-radius:34px;
    background:linear-gradient(135deg, #f3fffc, #ffffff);
    border:1px solid var(--line);
    box-shadow:var(--shadow);
}

.support-list{
    background:#fff;
    border:1px solid var(--line);
    border-radius:26px;
    padding:26px;
}

.support-list h3{
    font-size:22px;
    margin-bottom:14px;
}

.support-list ul{
    display:grid;
    gap:10px;
    color:var(--muted);
    padding-left:20px;
    margin-bottom:22px;
}

.footer{
    background:#0e1514;
    color:#fff;
    padding:38px 0 26px;
}

.footer-inner{
    display:flex;
    align-items:flex-start;
    justify-content:space-between;
    gap:24px;
    padding-bottom:24px;
    border-bottom:1px solid rgba(255,255,255,0.12);
}

.footer h3{
    margin-bottom:8px;
}

.footer p,
.footer a{
    color:rgba(255,255,255,0.72);
}

.footer-links{
    display:flex;
    gap:18px;
    flex-wrap:wrap;
}

.footer-copy{
    width:min(1120px, calc(100% - 40px));
    margin:20px auto 0;
    font-size:14px;
}

@media (max-width:980px){
    .guide-header-inner{
        min-height:auto;
        padding:18px 0;
        flex-direction:column;
        align-items:flex-start;
        gap:12px;
    }

    .quick-nav{
        width:100%;
        gap:18px;
        overflow-x:auto;
        padding-bottom:4px;
    }

    .hero-grid,
    .video-layout,
    .split-layout,
    .ai-layout,
    .support-box{
        grid-template-columns:1fr;
    }

    .step-grid,
    .use-grid,
    .ai-steps{
        grid-template-columns:1fr;
    }

    .hero{
        padding:58px 0 54px;
    }
}

@media (max-width:560px){
    .container,
    .guide-header-inner,
    .footer-copy{
        width:min(100% - 28px, 1120px);
    }

    .hero-copy h1{
        font-size:46px;
    }

    .support-box{
        padding:24px;
    }

    .footer-inner{
        flex-direction:column;
    }
}