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

:root {
    --accent: #E63946;
    --accent-dark: #C5303C;
    --carbon: #0A0A0A;
    --muted: #999999;
    --surface: #F5F5F5;
    --white: #FFFFFF;
    --font-serif: 'Noto Serif SC', 'Georgia', serif;
    --font-mono: 'DM Mono', 'Menlo', monospace;
}

html { scroll-behavior: smooth; }

body {
    font-family: var(--font-serif);
    line-height: 1.7;
    color: var(--carbon);
    background: var(--white);
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
    overflow-x: hidden;
}

::selection { background: var(--accent); color: #fff; }

a { color: inherit; text-decoration: none; }
ul { list-style: none; }
img { display: block; max-width: 100%; }

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 32px;
}

.text-accent { color: var(--accent); }

/* ========== Nav ========== */
.nav {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 100;
    background: rgba(255,255,255,0.92);
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    border-bottom: 1px solid transparent;
    transition: border-color 0.3s;
}
.nav.scrolled { border-bottom-color: #eee; }

.nav-inner {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 32px;
    height: 60px;
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.nav-logo {
    display: flex;
    align-items: center;
    gap: 8px;
}
.nav-logo-img { width: 28px; height: 28px; border-radius: 6px; }
.nav-logo-text {
    font-family: var(--font-serif);
    font-weight: 900;
    font-size: 18px;
    color: var(--carbon);
}

.nav-links { display: flex; gap: 24px; }
.nav-link {
    font-family: var(--font-mono);
    font-size: 12px;
    letter-spacing: 0.08em;
    text-transform: uppercase;
    color: var(--muted);
    transition: color 0.2s;
}
.nav-link:hover { color: var(--carbon); }

/* ========== Hero ========== */
.hero {
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    text-align: center;
    padding: 140px 32px 100px;
    position: relative;
    overflow: hidden;
}

.hero::before {
    content: '';
    position: absolute;
    width: 600px;
    height: 600px;
    background: radial-gradient(circle, rgba(230,57,70,0.06) 0%, transparent 70%);
    border-radius: 50%;
    top: -200px;
    left: 50%;
    transform: translateX(-50%);
    pointer-events: none;
}

.hero-tag {
    font-family: var(--font-mono);
    font-size: 13px;
    letter-spacing: 0.4em;
    text-transform: uppercase;
    color: var(--muted);
    margin-bottom: 48px;
}

.hero-title {
    font-family: var(--font-serif);
    font-weight: 900;
    font-size: clamp(3.2rem, 8vw, 6.4rem);
    line-height: 1.1;
    color: var(--carbon);
    margin-bottom: 32px;
    letter-spacing: -0.02em;
}

.hero-sub {
    font-size: 20px;
    font-weight: 400;
    color: var(--muted);
    max-width: 600px;
    margin: 0 auto 64px;
    line-height: 1.8;
}

.hero-stats {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 56px;
    margin-bottom: 64px;
}

.stat-divider { width: 1px; height: 48px; background: #e0e0e0; }

.stat { text-align: center; }
.stat-num {
    font-family: var(--font-mono);
    font-size: clamp(2.4rem, 5vw, 4rem);
    font-weight: 500;
    color: var(--carbon);
    font-variant-numeric: tabular-nums;
}
.stat-label {
    display: block;
    font-family: var(--font-mono);
    font-size: 12px;
    letter-spacing: 0.14em;
    color: var(--muted);
    margin-top: 8px;
}

.hero-actions { display: flex; gap: 20px; justify-content: center; flex-wrap: wrap; }

.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    font-family: var(--font-serif);
    font-size: 16px;
    font-weight: 700;
    padding: 16px 44px;
    border-radius: 999px;
    transition: all 0.25s;
    cursor: pointer;
    border: none;
    min-width: 172px;
}
.btn-primary { background: var(--accent); color: #fff; }
.btn-primary:hover { background: var(--accent-dark); transform: translateY(-2px); box-shadow: 0 8px 24px rgba(230,57,70,0.25); }
.btn-outline { background: transparent; color: var(--carbon); border: 2px solid var(--carbon); }
.btn-outline:hover { background: var(--carbon); color: #fff; transform: translateY(-2px); }

.hero-scroll-hint {
    position: absolute;
    bottom: 36px;
    left: 50%;
    transform: translateX(-50%);
    color: var(--muted);
    animation: bounce-hint 2.4s ease-in-out infinite;
}
@keyframes bounce-hint {
    0%, 100% { transform: translateX(-50%) translateY(0); }
    50% { transform: translateX(-50%) translateY(10px); }
}

/* ========== Section common ========== */
.section-head { margin-bottom: 64px; }
.section-tag {
    font-family: var(--font-mono);
    font-size: 11px;
    letter-spacing: 0.3em;
    text-transform: uppercase;
    color: var(--accent);
    margin-bottom: 12px;
}
.section-title {
    font-family: var(--font-serif);
    font-weight: 900;
    font-size: clamp(1.8rem, 4vw, 2.6rem);
    color: var(--carbon);
}
.section-sub {
    font-size: 14px;
    color: var(--muted);
    margin-top: 12px;
}

/* ========== Features ========== */
.features { padding: 120px 0; }

.feature-list { display: flex; flex-direction: column; }

.feature-row {
    display: flex;
    align-items: flex-start;
    gap: 40px;
    padding: 28px 16px;
    border-bottom: 1px solid #f0f0f0;
    transition: background 0.2s;
}
.feature-row:first-child { border-top: 1px solid #f0f0f0; }
.feature-row:hover { background: var(--surface); }

.feature-num {
    font-family: var(--font-mono);
    font-size: clamp(1.6rem, 3vw, 2.4rem);
    font-weight: 300;
    color: #ddd;
    min-width: 64px;
    transition: color 0.2s;
    user-select: none;
    line-height: 1;
    padding-top: 2px;
}
.feature-row:hover .feature-num { color: var(--accent); }

.feature-body { flex: 1; }
.feature-name {
    font-family: var(--font-serif);
    font-size: 18px;
    font-weight: 700;
    color: var(--carbon);
    margin-bottom: 6px;
}
.feature-desc {
    font-size: 14px;
    color: var(--muted);
    line-height: 1.7;
}

/* ========== Workflow ========== */
.workflow {
    padding: 120px 0;
    background: var(--surface);
}

.workflow-steps {
    display: flex;
    align-items: flex-start;
    justify-content: center;
    gap: 0;
}

.workflow-step {
    flex: 1;
    text-align: center;
    padding: 0 20px;
    position: relative;
}

.step-icon {
    width: 72px;
    height: 72px;
    border-radius: 20px;
    background: var(--white);
    display: flex;
    align-items: center;
    justify-content: center;
    margin: 0 auto 20px;
    color: var(--accent);
    box-shadow: 0 4px 16px rgba(0,0,0,0.06);
    border: 1px solid #eee;
}

.step-num {
    font-family: var(--font-mono);
    font-size: 11px;
    font-weight: 500;
    color: var(--accent);
    margin-bottom: 8px;
    letter-spacing: 0.1em;
}

.step-title {
    font-family: var(--font-serif);
    font-size: 18px;
    font-weight: 700;
    color: var(--carbon);
    margin-bottom: 8px;
}

.step-desc {
    font-size: 14px;
    color: var(--muted);
    line-height: 1.7;
    max-width: 240px;
    margin: 0 auto;
}

.workflow-connector {
    width: 60px;
    height: 2px;
    background: #ddd;
    margin-top: 36px;
    flex-shrink: 0;
    position: relative;
}
.workflow-connector::after {
    content: '';
    position: absolute;
    right: -3px;
    top: -3px;
    width: 8px;
    height: 8px;
    border-top: 2px solid #ddd;
    border-right: 2px solid #ddd;
    transform: rotate(45deg);
}

/* ========== Screenshots ========== */
.screenshots { padding: 120px 0; }

.screenshots-grid {
    display: flex;
    gap: 16px;
    overflow-x: auto;
    padding: 8px 4px 20px;
    scroll-snap-type: x mandatory;
    -webkit-overflow-scrolling: touch;
}
.screenshots-grid::-webkit-scrollbar {
    height: 4px;
}
.screenshots-grid::-webkit-scrollbar-track {
    background: #f0f0f0;
    border-radius: 2px;
}
.screenshots-grid::-webkit-scrollbar-thumb {
    background: #ccc;
    border-radius: 2px;
}

.screenshot-item {
    flex-shrink: 0;
    width: 240px;
    scroll-snap-align: center;
    text-align: center;
}
.screenshot-item img {
    width: 100%;
    height: auto;
    border-radius: 12px;
    box-shadow: 0 4px 16px rgba(0,0,0,0.08);
    border: 1px solid #eee;
    transition: transform 0.3s, box-shadow 0.3s;
}
.screenshot-item img:hover {
    transform: translateY(-4px);
    box-shadow: 0 8px 24px rgba(0,0,0,0.12);
}
.screenshot-label {
    display: block;
    margin-top: 10px;
    font-family: var(--font-mono);
    font-size: 12px;
    color: var(--muted);
    letter-spacing: 0.05em;
}

/* ========== Testimonials ========== */
.testimonials {
    padding: 120px 0;
    background: var(--surface);
}

.testimonial-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 24px;
}

.testimonial-card {
    background: var(--white);
    border: 1px solid #eee;
    border-radius: 16px;
    padding: 32px 24px;
    transition: border-color 0.25s, box-shadow 0.25s;
}
.testimonial-card:hover {
    border-color: rgba(230,57,70,0.2);
    box-shadow: 0 8px 32px rgba(230,57,70,0.06);
}

.testimonial-quote {
    font-size: 15px;
    color: var(--carbon);
    line-height: 1.8;
    margin-bottom: 24px;
    font-style: italic;
}

.testimonial-author {
    display: flex;
    align-items: center;
    gap: 12px;
}

.author-avatar {
    width: 40px;
    height: 40px;
    border-radius: 50%;
    background: var(--accent);
    color: #fff;
    display: flex;
    align-items: center;
    justify-content: center;
    font-family: var(--font-serif);
    font-weight: 700;
    font-size: 16px;
}

.author-name {
    font-family: var(--font-serif);
    font-size: 14px;
    font-weight: 700;
    color: var(--carbon);
}

.author-role {
    font-size: 12px;
    color: var(--muted);
}

/* ========== Download ========== */
.download {
    padding: 120px 0;
}

.download-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 32px;
    max-width: 800px;
    margin: 0 auto;
}

.dl-card {
    background: #fff;
    border: 1px solid #eee;
    border-radius: 16px;
    padding: 36px 28px;
    text-align: center;
    transition: border-color 0.25s, box-shadow 0.25s;
}
.dl-card:hover {
    border-color: rgba(230,57,70,0.25);
    box-shadow: 0 8px 32px rgba(230,57,70,0.06);
}

.dl-card-icon {
    width: 48px;
    height: 48px;
    border-radius: 12px;
    display: flex;
    align-items: center;
    justify-content: center;
    margin: 0 auto 24px;
}
.dl-card-icon--accent { background: rgba(230,57,70,0.08); color: var(--accent); }
.dl-card-icon--dark { background: rgba(10,10,10,0.04); color: var(--carbon); }

.dl-card-title {
    font-family: var(--font-serif);
    font-size: 18px;
    font-weight: 700;
    margin-bottom: 4px;
}
.dl-card-version {
    font-family: var(--font-mono);
    font-size: 12px;
    color: var(--muted);
    margin-bottom: 24px;
}
.dl-card-list {
    font-size: 13px;
    color: var(--muted);
    margin-bottom: 28px;
    line-height: 2;
}
.dl-card-btn { width: 100%; }

/* ========== FAQ ========== */
.faq { padding: 120px 0; background: var(--surface); }

.faq-list { max-width: 800px; margin: 0 auto; }

.faq-item {
    border-bottom: 1px solid #e0e0e0;
}
.faq-item:first-child { border-top: 1px solid #e0e0e0; }

.faq-question {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 20px 8px;
    cursor: pointer;
    transition: color 0.2s;
    user-select: none;
}
.faq-question span {
    font-family: var(--font-serif);
    font-size: 16px;
    font-weight: 700;
    color: var(--carbon);
}
.faq-question:hover span { color: var(--accent); }

.faq-arrow {
    flex-shrink: 0;
    color: var(--muted);
    transition: transform 0.3s, color 0.3s;
}
.faq-item.active .faq-arrow {
    transform: rotate(180deg);
    color: var(--accent);
}

.faq-answer {
    max-height: 0;
    overflow: hidden;
    transition: max-height 0.4s ease, padding 0.4s ease;
}
.faq-item.active .faq-answer {
    max-height: 200px;
}
.faq-answer p {
    font-size: 14px;
    color: var(--muted);
    line-height: 1.8;
    padding: 0 8px 20px;
}

/* ========== About ========== */
.about { padding: 120px 0; }

.about-inner { text-align: center; }

.about-slogan {
    font-family: var(--font-serif);
    font-weight: 900;
    font-size: clamp(1.6rem, 4vw, 2.4rem);
    color: var(--carbon);
    line-height: 1.5;
    margin-bottom: 48px;
}

.about-contacts {
    display: flex;
    justify-content: center;
    gap: 32px;
    flex-wrap: wrap;
}

.about-contact {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    font-family: var(--font-mono);
    font-size: 13px;
    color: var(--muted);
    transition: color 0.2s;
}
.about-contact:hover { color: var(--accent); }

/* ========== Footer ========== */
.footer { padding: 48px 0; }

.footer-line {
    width: 48px;
    height: 1px;
    background: #e0e0e0;
    margin: 0 auto 24px;
}

.footer-content { text-align: center; }

.footer-links {
    display: flex;
    justify-content: center;
    align-items: center;
    gap: 12px;
    margin-bottom: 16px;
}
.footer-links a {
    font-family: var(--font-mono);
    font-size: 12px;
    color: #999;
    transition: color 0.2s;
}
.footer-links a:hover { color: var(--accent); }
.footer-divider { color: #ddd; font-size: 12px; }

.footer-copy {
    font-family: var(--font-mono);
    font-size: 11px;
    color: #ccc;
    letter-spacing: 0.06em;
}

/* ========== Scenarios ========== */
.scenarios { padding: 120px 0; background: var(--surface); }

.scenario-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 24px;
}

.scenario-card {
    background: var(--white);
    border: 1px solid #eee;
    border-radius: 16px;
    padding: 32px 24px;
    text-align: center;
    transition: border-color 0.25s, box-shadow 0.25s, transform 0.25s;
}
.scenario-card:hover {
    border-color: rgba(230,57,70,0.25);
    box-shadow: 0 8px 32px rgba(230,57,70,0.06);
    transform: translateY(-4px);
}

.scenario-icon {
    width: 64px;
    height: 64px;
    border-radius: 16px;
    background: rgba(230,57,70,0.06);
    display: flex;
    align-items: center;
    justify-content: center;
    margin: 0 auto 20px;
    color: var(--accent);
}

.scenario-title {
    font-family: var(--font-serif);
    font-size: 18px;
    font-weight: 700;
    color: var(--carbon);
    margin-bottom: 12px;
}

.scenario-desc {
    font-size: 14px;
    color: var(--muted);
    line-height: 1.7;
    margin-bottom: 16px;
}

.scenario-tag {
    display: inline-block;
    padding: 4px 14px;
    background: rgba(230,57,70,0.06);
    color: var(--accent);
    border-radius: 999px;
    font-family: var(--font-mono);
    font-size: 11px;
    letter-spacing: 0.06em;
}

/* ========== Advantages ========== */
.advantages { padding: 120px 0; }

.adv-table {
    max-width: 800px;
    margin: 0 auto;
    border: 1px solid #eee;
    border-radius: 12px;
    overflow: hidden;
}

.adv-header {
    display: flex;
    background: var(--carbon);
    color: var(--white);
    font-family: var(--font-mono);
    font-size: 12px;
    letter-spacing: 0.06em;
}

.adv-header .adv-col-feature { flex: 1.2; }
.adv-header .adv-col-us { flex: 1.4; color: var(--accent); font-weight: 500; }
.adv-header .adv-col-other { flex: 1.4; opacity: 0.6; }

.adv-row {
    display: flex;
    border-bottom: 1px solid #f0f0f0;
    transition: background 0.2s;
}
.adv-row:last-child { border-bottom: none; }
.adv-row:hover { background: rgba(230,57,70,0.02); }

.adv-col {
    padding: 16px 20px;
    font-size: 14px;
    color: var(--carbon);
}

.adv-col-feature {
    flex: 1.2;
    font-weight: 700;
    font-family: var(--font-serif);
    font-size: 13px;
    color: var(--carbon);
}

.adv-col-us {
    flex: 1.4;
    font-size: 13px;
    color: var(--carbon);
}

.adv-col-other {
    flex: 1.4;
    font-size: 13px;
    color: var(--muted);
}

.adv-check {
    color: var(--accent);
    font-weight: 700;
    margin-right: 6px;
}

/* ========== Changelog ========== */
.changelog {
    padding: 120px 0;
    background: var(--surface);
}

.changelog-timeline {
    max-width: 600px;
    margin: 0 auto;
    position: relative;
}

.changelog-timeline::before {
    content: '';
    position: absolute;
    left: 11px;
    top: 0;
    bottom: 0;
    width: 2px;
    background: #e0e0e0;
}

.changelog-item {
    display: flex;
    align-items: flex-start;
    gap: 24px;
    padding-bottom: 48px;
    position: relative;
}
.changelog-item:last-child { padding-bottom: 0; }

.changelog-dot {
    width: 24px;
    height: 24px;
    border-radius: 50%;
    background: var(--white);
    border: 3px solid var(--accent);
    flex-shrink: 0;
    position: relative;
    z-index: 1;
}

.changelog-version {
    font-family: var(--font-mono);
    font-size: 16px;
    font-weight: 500;
    color: var(--accent);
    margin-bottom: 4px;
}

.changelog-date {
    font-family: var(--font-mono);
    font-size: 12px;
    color: var(--muted);
    margin-bottom: 12px;
}

.changelog-list {
    list-style: none;
    padding: 0;
}

.changelog-list li {
    font-size: 14px;
    color: var(--carbon);
    line-height: 1.8;
    padding-left: 16px;
    position: relative;
}
.changelog-list li::before {
    content: '+';
    position: absolute;
    left: 0;
    color: var(--accent);
    font-weight: 700;
}

/* ========== Scroll reveal ==========*/
.fade-up {
    opacity: 0;
    transform: translateY(32px);
    transition: opacity 0.8s cubic-bezier(0.16, 1, 0.3, 1),
                transform 0.8s cubic-bezier(0.16, 1, 0.3, 1);
}
.fade-up.visible {
    opacity: 1;
    transform: translateY(0);
}

/* ========== Responsive ========== */
@media (max-width: 768px) {
    .nav-links { gap: 10px; }
    .nav-link { font-size: 11px; }

    .hero { padding-top: 80px; padding-bottom: 40px; }
    .hero-stats { gap: 20px; }
    .stat-num { font-size: 2rem; }
    .hero-actions { flex-wrap: wrap; justify-content: center; }

    /* 各section缩小padding */
    .features, .download, .about, .workflow, .screenshots, .testimonials, .faq,
    .scenarios, .advantages, .changelog { padding: 60px 0; }

    /* 功能列表 → 2列网格 */
    .feature-list { display: grid; grid-template-columns: repeat(2, 1fr); gap: 12px; }
    .feature-row { gap: 8px; padding: 16px 12px; flex-direction: column; align-items: center; text-align: center; }
    .feature-num { min-width: unset; font-size: 1.2rem; margin-bottom: 4px; }
    .feature-name { font-size: 15px; }
    .feature-desc { font-size: 12px; line-height: 1.5; }

    /* 工作流 → 横排紧凑 */
    .workflow-steps { gap: 8px; }
    .workflow-step { padding: 16px 8px; }
    .workflow-step h3 { font-size: 14px; }
    .workflow-step p { font-size: 11px; }
    .step-icon { width: 40px; height: 40px; font-size: 18px; }
    .workflow-connector { margin-top: 0; }
    .workflow-connector::after { font-size: 16px; }

    /* 场景 → 2列 */
    .scenario-grid { grid-template-columns: repeat(2, 1fr); gap: 12px; }
    .scenario-card { padding: 20px 16px; }
    .scenario-icon { width: 48px; height: 48px; margin-bottom: 12px; }
    .scenario-title { font-size: 15px; }
    .scenario-desc { font-size: 12px; }

    /* 评价 → 2列 */
    .testimonial-grid { grid-template-columns: repeat(2, 1fr); gap: 12px; }
    .testimonial-card { padding: 16px; }
    .testimonial-quote { font-size: 13px; }

    /* 优势对比 */
    .adv-table { font-size: 12px; }
    .adv-col { padding: 10px 12px; font-size: 12px; }

    /* 下载 → 2列 */
    .download-grid { grid-template-columns: 1fr 1fr; gap: 12px; max-width: 100%; }
    .dl-card { padding: 20px 16px; }
    .dl-card-title { font-size: 16px; }
    .dl-card-list { font-size: 12px; line-height: 1.8; margin-bottom: 16px; }

    /* FAQ */
    .faq-question span { font-size: 14px; }
    .faq-answer p { font-size: 13px; }
}

@media (max-width: 480px) {
    .hero-stats { gap: 12px; }
    .stat-num { font-size: 1.4rem; }
    .stat-label { font-size: 11px; }
    .stat-divider { height: 24px; }

    .scenario-grid { grid-template-columns: repeat(2, 1fr); gap: 8px; }
    .scenario-card { padding: 16px 12px; }

    .feature-list { gap: 8px; }
    .feature-row { padding: 12px 8px; }

    .testimonial-grid { gap: 8px; }

    .download-grid { gap: 8px; }
    .dl-card { padding: 16px 12px; }

    .adv-col { padding: 8px 8px; font-size: 11px; }
    .adv-col-feature { font-size: 11px; }

    .nav-links { gap: 8px; }
    .nav-link { font-size: 10px; }
}