/* ============================================
   YYGEL Biotechnology - 全局样式
   主题: 现代渐变 (深绿 #0F766E → 青 #06B6D4)
   ============================================ */

:root {
    --c-primary: #0f766e;
    --c-primary-light: #14b8a6;
    --c-accent: #06b6d4;
    --c-accent-light: #22d3ee;
    --c-bg: #0a1f1d;
    --c-bg-2: #0e2a28;
    --c-bg-3: #133634;
    --c-text: #f0fdfa;
    --c-text-soft: #99f6e4;
    --c-text-muted: #5eead4;
    --c-border: rgba(94, 234, 212, 0.12);
    --c-glass: rgba(15, 118, 110, 0.15);

    --gradient: linear-gradient(135deg, #0f766e 0%, #06b6d4 100%);
    --gradient-soft: linear-gradient(
        135deg,
        rgba(15, 118, 110, 0.15),
        rgba(6, 182, 212, 0.15)
    );
    --gradient-text: linear-gradient(
        135deg,
        #5eead4 0%,
        #22d3ee 50%,
        #67e8f9 100%
    );

    --shadow-glow: 0 0 40px rgba(6, 182, 212, 0.25);
    --shadow-card: 0 20px 50px -20px rgba(0, 0, 0, 0.5);
    --shadow-hover: 0 25px 60px -20px rgba(6, 182, 212, 0.4);

    --r-sm: 8px;
    --r-md: 14px;
    --r-lg: 20px;
    --r-xl: 28px;

    --container: 1240px;
    --nav-h: 76px;
}

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

html {
    scroll-behavior: smooth;
}

body {
    font-family:
        "Inter",
        "Noto Sans SC",
        -apple-system,
        BlinkMacSystemFont,
        "Segoe UI",
        sans-serif;
    background: var(--c-bg);
    color: var(--c-text);
    line-height: 1.6;
    overflow-x: hidden;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
    forced-color-adjust: none;
}

img {
    max-width: 100%;
    display: block;
}
a {
    color: inherit;
    text-decoration: none;
}
button {
    font-family: inherit;
    cursor: pointer;
    border: none;
    background: none;
    color: inherit;
}
ul {
    list-style: none;
}

.container {
    max-width: var(--container);
    margin: 0 auto;
    padding: 0 32px;
    position: relative;
}

/* 粒子背景 */
.particles {
    position: fixed;
    inset: 0;
    pointer-events: none;
    z-index: 0;
    overflow: hidden;
}
.particle {
    position: absolute;
    border-radius: 50%;
    background: var(--gradient);
    opacity: 0;
    animation: floatUp 18s linear infinite;
    filter: blur(0.5px);
}
@keyframes floatUp {
    0% {
        transform: translateY(110vh) translateX(0) scale(0);
        opacity: 0;
    }
    10% {
        opacity: 0.5;
    }
    90% {
        opacity: 0.3;
    }
    100% {
        transform: translateY(-10vh) translateX(40px) scale(1);
        opacity: 0;
    }
}

/* 通用 */
.section {
    padding: 120px 0;
    position: relative;
}
.section-head {
    text-align: center;
    max-width: 760px;
    margin: 0 auto 72px;
}
.section-eyebrow {
    display: inline-block;
    font-size: 13px;
    font-weight: 600;
    letter-spacing: 4px;
    color: var(--c-accent);
    padding: 6px 16px;
    border: 1px solid var(--c-border);
    border-radius: 100px;
    background: var(--gradient-soft);
    margin-bottom: 24px;
    text-transform: uppercase;
}
.section-title {
    font-size: clamp(32px, 4.5vw, 52px);
    font-weight: 800;
    line-height: 1.15;
    margin-bottom: 20px;
    letter-spacing: -0.02em;
}
.section-sub {
    font-size: 17px;
    color: var(--c-text-soft);
    line-height: 1.7;
}
.gradient-text {
    background: var(--gradient-text);
    -webkit-background-clip: text;
    background-clip: text;
    -webkit-text-fill-color: transparent;
    color: transparent;
    display: inline-block;
}

/* 按钮 */
.btn {
    display: inline-flex;
    align-items: center;
    gap: 10px;
    padding: 14px 30px;
    border-radius: 100px;
    font-weight: 600;
    font-size: 15px;
    letter-spacing: 0.02em;
    transition: all 0.35s cubic-bezier(0.4, 0, 0.2, 1);
    position: relative;
    overflow: hidden;
    white-space: nowrap;
}
.btn svg {
    width: 18px;
    height: 18px;
    transition: transform 0.35s;
}
.btn:hover svg {
    transform: translateX(4px);
}
.btn-primary {
    background: var(--gradient);
    color: #fff;
    box-shadow: 0 8px 30px -8px rgba(6, 182, 212, 0.6);
}
.btn-primary::before {
    content: "";
    position: absolute;
    inset: 0;
    background: linear-gradient(135deg, #06b6d4 0%, #0f766e 100%);
    opacity: 0;
    transition: opacity 0.35s;
}
.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 12px 40px -8px rgba(6, 182, 212, 0.8);
}
.btn-primary:hover::before {
    opacity: 1;
}
.btn-primary span,
.btn-primary svg {
    position: relative;
    z-index: 1;
}
.btn-ghost {
    background: transparent;
    color: var(--c-text);
    border: 1px solid var(--c-border);
    backdrop-filter: blur(10px);
}
.btn-ghost:hover {
    background: var(--gradient-soft);
    border-color: var(--c-accent);
}
.btn-block {
    width: 100%;
    justify-content: center;
}

/* 导航栏 */
.header {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 100;
    height: var(--nav-h);
    transition: all 0.35s;
    background: transparent;
}
.header.scrolled {
    background: rgba(10, 31, 29, 0.75);
    backdrop-filter: blur(20px) saturate(150%);
    border-bottom: 1px solid var(--c-border);
    box-shadow: 0 8px 30px rgba(0, 0, 0, 0.2);
}
.nav {
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 100%;
}
.logo {
    display: flex;
    align-items: center;
    gap: 12px;
    font-weight: 800;
}
.logo-mark {
    width: 42px;
    height: 42px;
    display: flex;
    align-items: center;
    justify-content: center;
    filter: drop-shadow(0 0 8px rgba(6, 182, 212, 0.5));
}
.logo-mark svg {
    width: 100%;
    height: 100%;
}
.logo-text {
    display: flex;
    flex-direction: column;
    line-height: 1.1;
}
.logo-name {
    font-size: 20px;
    font-weight: 800;
    background: var(--gradient-text);
    -webkit-background-clip: text;
    background-clip: text;
    -webkit-text-fill-color: transparent;
    letter-spacing: 0.05em;
}
.logo-tagline {
    font-size: 10px;
    font-weight: 500;
    color: var(--c-text-muted);
    letter-spacing: 0.25em;
    text-transform: uppercase;
    margin-top: 2px;
}
.nav-menu {
    display: flex;
    align-items: center;
    gap: 4px;
}
.nav-link {
    padding: 10px 18px;
    font-size: 14.5px;
    font-weight: 500;
    color: var(--c-text-soft);
    border-radius: 100px;
    transition: all 0.3s;
    position: relative;
}
.nav-link:hover {
    color: var(--c-text);
    background: var(--gradient-soft);
}
.nav-actions {
    display: flex;
    align-items: center;
    gap: 12px;
}
.lang-toggle {
    display: flex;
    align-items: center;
    gap: 6px;
    padding: 8px 14px;
    border: 1px solid var(--c-border);
    border-radius: 100px;
    font-size: 13px;
    font-weight: 600;
    color: var(--c-text-soft);
    transition: all 0.3s;
    background: var(--gradient-soft);
}
.lang-toggle svg {
    width: 16px;
    height: 16px;
}
.lang-toggle:hover {
    color: var(--c-text);
    border-color: var(--c-accent);
}
.menu-toggle {
    display: none;
    flex-direction: column;
    gap: 5px;
    padding: 10px;
}
.menu-toggle span {
    width: 22px;
    height: 2px;
    background: var(--c-text);
    border-radius: 2px;
    transition: 0.3s;
}

/* Hero */
.hero {
    position: relative;
    min-height: auto;
    display: flex;
    align-items: center;
    overflow: hidden;
    padding-top: calc(var(--nav-h) + 60px);
    padding-bottom: 80px;
}
.hero-bg {
    position: absolute;
    inset: 0;
    z-index: 0;
}
.hero-bg::before {
    content: "";
    position: absolute;
    inset: 0;
    background:
        radial-gradient(
            ellipse 80% 60% at 70% 20%,
            rgba(6, 182, 212, 0.35) 0%,
            transparent 60%
        ),
        radial-gradient(
            ellipse 60% 50% at 20% 80%,
            rgba(15, 118, 110, 0.4) 0%,
            transparent 60%
        ),
        linear-gradient(180deg, #0a1f1d 0%, #0e2a28 100%);
}
.hero-overlay {
    position: absolute;
    inset: 0;
    background: linear-gradient(
        180deg,
        transparent 0%,
        rgba(10, 31, 29, 0.4) 100%
    );
}
.hero-grid {
    position: absolute;
    inset: 0;
    background-image:
        linear-gradient(rgba(94, 234, 212, 0.04) 1px, transparent 1px),
        linear-gradient(90deg, rgba(94, 234, 212, 0.04) 1px, transparent 1px);
    background-size: 60px 60px;
    mask-image: radial-gradient(
        ellipse 70% 60% at 50% 50%,
        black 30%,
        transparent 80%
    );
    -webkit-mask-image: radial-gradient(
        ellipse 70% 60% at 50% 50%,
        black 30%,
        transparent 80%
    );
}
.hero-content {
    position: relative;
    z-index: 2;
    text-align: center;
    max-width: 960px;
}

@keyframes pulse {
    0%,
    100% {
        opacity: 1;
        transform: scale(1);
    }
    50% {
        opacity: 0.6;
        transform: scale(1.2);
    }
}
.hero-title {
    font-size: clamp(40px, 7vw, 84px);
    font-weight: 900;
    line-height: 1.05;
    margin-bottom: 28px;
    letter-spacing: -0.03em;
}
.title-line {
    display: block;
}
.hero-desc {
    font-size: 18px;
    color: var(--c-text-soft);
    max-width: 680px;
    margin: 0 auto 40px;
    line-height: 1.7;
}
.hero-cta {
    display: flex;
    justify-content: center;
    gap: 16px;
    flex-wrap: wrap;
    margin-bottom: 0px;
}
.hero-stats {
    display: flex;
    justify-content: center;
    gap: 60px;
    flex-wrap: wrap;
    padding-top: 40px;
    border-top: 1px solid var(--c-border);
}
.stat {
    text-align: center;
    display: flex;
    align-items: baseline;
    justify-content: center;
    gap: 4px;
}
.stat-num {
    font-size: 56px;
    font-weight: 800;
    line-height: 1;
    background: var(--gradient-text);
    -webkit-background-clip: text;
    background-clip: text;
    -webkit-text-fill-color: transparent;
    letter-spacing: -0.02em;
}
.stat-plus {
    font-size: 32px;
    font-weight: 700;
    color: var(--c-accent);
}
.stat-label {
    flex: 0 0 100%;
    margin-top: 8px;
    font-size: 13px;
    color: var(--c-text-muted);
    letter-spacing: 0.1em;
    text-transform: uppercase;
}

/* 信任带 */

/* About */
.about {
    background: linear-gradient(180deg, var(--c-bg) 0%, var(--c-bg-2) 100%);
}
.about-grid {
    display: grid;
    grid-template-columns: 1fr 1.2fr;
    gap: 80px;
    align-items: center;
}
.about-visual {
    position: relative;
    aspect-ratio: 1;
    max-width: 480px;
    margin: 0 auto;
}
.visual-card {
    position: relative;
    width: 100%;
    height: 100%;
    border-radius: var(--r-xl);
    background: var(--gradient-soft);
    border: 1px solid var(--c-border);
    overflow: hidden;
    display: flex;
    align-items: center;
    justify-content: center;
    box-shadow: var(--shadow-glow);
}
.visual-orb {
    position: absolute;
    width: 60%;
    height: 60%;
    background: radial-gradient(
        circle,
        rgba(6, 182, 212, 0.6) 0%,
        transparent 70%
    );
    border-radius: 50%;
    filter: blur(30px);
    animation: orbFloat 8s ease-in-out infinite;
}
@keyframes orbFloat {
    0%,
    100% {
        transform: translate(0, 0) scale(1);
    }
    33% {
        transform: translate(20px, -20px) scale(1.1);
    }
    66% {
        transform: translate(-20px, 20px) scale(0.95);
    }
}
.visual-ring {
    position: absolute;
    border-radius: 50%;
    border: 1px dashed rgba(94, 234, 212, 0.3);
}
.visual-ring.r1 {
    width: 70%;
    height: 70%;
    animation: spin 20s linear infinite;
}
.visual-ring.r2 {
    width: 85%;
    height: 85%;
    border-style: dotted;
    animation: spin 30s linear infinite reverse;
    border-color: rgba(6, 182, 212, 0.25);
}
.visual-ring.r3 {
    width: 100%;
    height: 100%;
    animation: spin 40s linear infinite;
    border-color: rgba(15, 118, 110, 0.3);
}
@keyframes spin {
    to {
        transform: rotate(360deg);
    }
}
.visual-label {
    position: relative;
    z-index: 2;
    text-align: center;
}
.visual-label .big {
    display: block;
    font-size: 56px;
    font-weight: 900;
    background: var(--gradient-text);
    -webkit-background-clip: text;
    background-clip: text;
    -webkit-text-fill-color: transparent;
    letter-spacing: 0.05em;
    line-height: 1;
    margin-bottom: 8px;
}
.visual-label .small {
    font-size: 12px;
    color: var(--c-text-muted);
    letter-spacing: 0.2em;
    text-transform: uppercase;
}

.about-text {
    display: flex;
    flex-direction: column;
    gap: 28px;
}
.about-item {
    display: flex;
    flex-wrap: wrap;
    align-items: flex-start;
    gap: 20px;
    padding: 24px;
    border-radius: var(--r-md);
    background: rgba(15, 118, 110, 0.05);
    border: 1px solid var(--c-border);
    transition: all 0.35s;
}
.about-item h3,
.about-item p {
    flex: 1 1 calc(100% - 76px);
    min-width: 0;
}
.about-item:hover {
    background: var(--gradient-soft);
    transform: translateX(8px);
    border-color: var(--c-accent);
}
.about-icon {
    width: 56px;
    height: 56px;
    border-radius: var(--r-sm);
    background: var(--gradient);
    display: flex;
    align-items: center;
    justify-content: center;
    box-shadow: 0 8px 20px -5px rgba(6, 182, 212, 0.4);
}
.about-icon svg {
    width: 28px;
    height: 28px;
    color: #fff;
}
.about-item h3 {
    font-size: 20px;
    font-weight: 700;
    margin-bottom: 6px;
}
.about-item p {
    color: var(--c-text-soft);
    font-size: 15px;
    line-height: 1.7;
}

/* Products */
.products {
    background: var(--c-bg-2);
}

.product-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
    gap: 28px;
}
.product-card {
    background: var(--c-bg);
    border: 1px solid var(--c-border);
    border-radius: var(--r-lg);
    overflow: hidden;
    transition: all 0.4s cubic-bezier(0.4, 0, 0.2, 1);
    position: relative;
}
.product-card:hover {
    transform: translateY(-8px);
    border-color: var(--c-accent);
    box-shadow: var(--shadow-hover);
}
.product-card.hidden {
    display: none;
}
.product-img {
    height: 180px;
    position: relative;
    background: linear-gradient(135deg, #0f766e 0%, #06b6d4 100%);
    overflow: hidden;
    display: flex;
    align-items: center;
    justify-content: center;
}
.product-icon {
    position: relative;
    z-index: 2;
    width: 72px;
    height: 72px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: rgba(255, 255, 255, 0.12);
    border-radius: 20px;
    backdrop-filter: blur(8px);
    border: 1px solid rgba(255, 255, 255, 0.2);
    box-shadow: 0 8px 32px rgba(0, 0, 0, 0.2);
}
.product-icon svg {
    width: 36px;
    height: 36px;
    color: #fff;
}

.gel-blob {
    position: absolute;
    width: 200px;
    height: 200px;
    border-radius: 50%;
    filter: blur(40px);
    opacity: 0.5;
    animation: blobFloat 6s ease-in-out infinite;
}
.gel-blob.g1 {
    background: #06b6d4;
    top: 20%;
    left: 30%;
}
.gel-blob.g2 {
    background: #22d3ee;
    top: 30%;
    right: 20%;
    animation-delay: -2s;
}
.gel-blob.g3 {
    background: #14b8a6;
    bottom: 20%;
    left: 40%;
    animation-delay: -4s;
}
@keyframes blobFloat {
    0%,
    100% {
        transform: translate(0, 0) scale(1);
    }
    50% {
        transform: translate(20px, -20px) scale(1.15);
    }
}

.product-body {
    padding: 28px 28px 24px;
    text-align: center;
}

.product-body h3 {
    font-size: 20px;
    font-weight: 700;
    margin-bottom: 8px;
    letter-spacing: -0.01em;
}

.product-subtitle {
    display: block;
    font-size: 13px;
    font-weight: 600;
    color: var(--c-text-muted);
    letter-spacing: 0.08em;
    text-transform: uppercase;
    margin-bottom: 20px;
}

.product-accent {
    width: 40px;
    height: 3px;
    border-radius: 2px;
    background: var(--gradient);
    margin: 0 auto;
    transition: width 0.4s ease;
}

.product-card:hover .product-accent {
    width: 80px;
}

/* Advantages */
.advantages {
    background: linear-gradient(180deg, var(--c-bg-2) 0%, var(--c-bg) 100%);
}
.adv-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
    gap: 24px;
}
.adv-card {
    background: var(--c-bg-2);
    border: 1px solid var(--c-border);
    border-radius: var(--r-lg);
    padding: 32px 28px;
    transition: all 0.4s;
    position: relative;
    overflow: hidden;
}
.adv-card::before {
    content: "";
    position: absolute;
    inset: 0;
    background: var(--gradient);
    opacity: 0;
    transition: opacity 0.4s;
    z-index: 0;
}
.adv-card:hover {
    transform: translateY(-6px);
    border-color: var(--c-accent);
}
.adv-card:hover::before {
    opacity: 0.08;
}
.adv-card > * {
    position: relative;
    z-index: 1;
}
.adv-num {
    font-size: 36px;
    font-weight: 900;
    background: var(--gradient-text);
    -webkit-background-clip: text;
    background-clip: text;
    -webkit-text-fill-color: transparent;
    line-height: 1;
    margin-bottom: 16px;
    letter-spacing: -0.02em;
}
.adv-card h3 {
    font-size: 20px;
    font-weight: 700;
    margin-bottom: 12px;
}
.adv-card p {
    color: var(--c-text-soft);
    font-size: 14.5px;
    line-height: 1.7;
    margin-bottom: 24px;
}
.adv-bar {
    height: 4px;
    background: var(--c-bg-3);
    border-radius: 2px;
    overflow: hidden;
}
.adv-bar span {
    display: block;
    height: 100%;
    width: 0;
    background: var(--gradient);
    border-radius: 2px;
    transition: width 1.5s ease-out;
}
.adv-card.reveal.in-view .adv-bar span {
    width: var(--w);
}

/* Applications */
.applications {
    background: var(--c-bg);
}
.app-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
    gap: 20px;
}

.app-card {
    background: var(--gradient-soft);
    border: 1px solid var(--c-border);
    border-radius: var(--r-md);
    padding: 32px 24px 28px;
    text-align: center;
    transition: all 0.35s;
    position: relative;
    overflow: hidden;
}

.app-card::after {
    content: "";
    position: absolute;
    top: -50%;
    left: -50%;
    width: 200%;
    height: 200%;
    background: radial-gradient(
        circle,
        rgba(6, 182, 212, 0.1) 0%,
        transparent 60%
    );
    opacity: 0;
    transition: opacity 0.4s;
}

.app-card:hover {
    transform: translateY(-4px);
    border-color: var(--c-accent);
}

.app-card:hover::after {
    opacity: 1;
}

.app-icon {
    width: 64px;
    height: 64px;
    margin: 0 auto 20px;
    border-radius: 16px;
    background: var(--gradient);
    display: flex;
    align-items: center;
    justify-content: center;
    box-shadow: 0 8px 20px -5px rgba(6, 182, 212, 0.4);
    position: relative;
    z-index: 1;
}

.app-icon svg {
    width: 30px;
    height: 30px;
    color: #fff;
}

.app-card h3 {
    font-size: 18px;
    font-weight: 700;
    margin-bottom: 6px;
    position: relative;
    z-index: 1;
}

.app-subtitle {
    display: block;
    font-size: 13px;
    font-weight: 600;
    color: var(--c-text-muted);
    letter-spacing: 0.06em;
    text-transform: uppercase;
    margin-bottom: 16px;
    position: relative;
    z-index: 1;
}

.app-accent {
    width: 32px;
    height: 3px;
    border-radius: 2px;
    background: var(--gradient);
    margin: 0 auto;
    position: relative;
    z-index: 1;
    transition: width 0.4s ease;
}

.app-card:hover .app-accent {
    width: 64px;
}

/* Process */

/* Contact */
.contact {
    background: linear-gradient(180deg, var(--c-bg) 0%, var(--c-bg-2) 100%);
}
.contact-wrap {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 60px;
    align-items: start;
}
.contact-title {
    font-size: clamp(32px, 4vw, 48px);
    font-weight: 800;
    line-height: 1.15;
    margin: 20px 0 24px;
    letter-spacing: -0.02em;
}
.contact-info > p {
    color: var(--c-text-soft);
    margin-bottom: 36px;
    line-height: 1.7;
    font-size: 16px;
}
.contact-list {
    display: flex;
    flex-direction: column;
    gap: 24px;
}
.contact-list li {
    display: grid;
    grid-template-columns: 48px 1fr;
    gap: 16px;
    align-items: start;
}
.ci-icon {
    width: 48px;
    height: 48px;
    border-radius: 12px;
    background: var(--gradient-soft);
    border: 1px solid var(--c-border);
    display: flex;
    align-items: center;
    justify-content: center;
}
.ci-icon svg {
    width: 22px;
    height: 22px;
    color: var(--c-accent);
}
.contact-list strong {
    display: block;
    color: var(--c-text);
    font-size: 14px;
    font-weight: 700;
    margin-bottom: 4px;
    letter-spacing: 0.05em;
}
.contact-list span {
    color: var(--c-text-soft);
    font-size: 14.5px;
    line-height: 1.6;
}

.contact-form {
    background: var(--c-bg-3);
    border: 1px solid var(--c-border);
    border-radius: var(--r-lg);
    padding: 40px;
    box-shadow: var(--shadow-card);
}
.contact-form h3 {
    font-size: 22px;
    font-weight: 700;
    margin-bottom: 24px;
}
.form-row {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 16px;
    margin-bottom: 16px;
}
.form-field {
    display: flex;
    flex-direction: column;
    margin-bottom: 16px;
}
.form-field label {
    font-size: 12px;
    font-weight: 600;
    color: var(--c-text-muted);
    margin-bottom: 8px;
    letter-spacing: 0.08em;
    text-transform: uppercase;
}
.form-field input,
.form-field select,
.form-field textarea {
    padding: 12px 16px;
    background: var(--c-bg);
    border: 1px solid var(--c-border);
    border-radius: var(--r-sm);
    color: var(--c-text);
    font-size: 14.5px;
    font-family: inherit;
    transition: all 0.3s;
    outline: none;
    resize: vertical;
}
.form-field input:focus,
.form-field select:focus,
.form-field textarea:focus {
    border-color: var(--c-accent);
    box-shadow: 0 0 0 3px rgba(6, 182, 212, 0.15);
}
.form-field select {
    appearance: none;
    background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='14' height='14' viewBox='0 0 24 24' fill='none' stroke='%2306B6D4' stroke-width='2'%3E%3Cpath d='M6 9l6 6 6-6'/%3E%3C/svg%3E");
    background-repeat: no-repeat;
    background-position: right 14px center;
    padding-right: 40px;
}
.form-field select option {
    background: var(--c-bg-2);
}
.form-status {
    margin-top: 16px;
    padding: 10px 16px;
    border-radius: var(--r-sm);
    font-size: 14px;
    text-align: center;
    display: none;
}
.form-status.success {
    display: block;
    background: rgba(34, 197, 94, 0.15);
    border: 1px solid rgba(34, 197, 94, 0.3);
    color: #4ade80;
}
.form-status.error {
    display: block;
    background: rgba(239, 68, 68, 0.15);
    border: 1px solid rgba(239, 68, 68, 0.3);
    color: #f87171;
}

/* Footer */
.footer {
    background: #051612;
    border-top: 1px solid var(--c-border);
    padding-top: 60px;
}
.footer-inner {
    display: grid;
    grid-template-columns: 1.5fr 2fr;
    gap: 60px;
    padding-bottom: 48px;
}
.footer-brand .logo {
    margin-bottom: 20px;
}
.footer-brand p {
    color: var(--c-text-soft);
    line-height: 1.7;
    font-size: 14.5px;
    max-width: 320px;
}
.footer-cols {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 40px;
}
.footer-col h4 {
    font-size: 13px;
    font-weight: 700;
    letter-spacing: 0.1em;
    text-transform: uppercase;
    color: var(--c-text);
    margin-bottom: 18px;
}
.footer-col a {
    display: block;
    color: var(--c-text-soft);
    font-size: 14.5px;
    margin-bottom: 10px;
    transition: color 0.3s;
}
.footer-col a:hover {
    color: var(--c-accent);
}
.footer-bottom {
    border-top: 1px solid var(--c-border);
    padding: 24px 0;
    font-size: 13px;
    color: var(--c-text-muted);
}
.footer-bottom .container {
    display: flex;
    justify-content: space-between;
    flex-wrap: wrap;
    gap: 8px;
}

/* 回到顶部 */
.to-top {
    position: fixed;
    bottom: 30px;
    right: 30px;
    width: 48px;
    height: 48px;
    border-radius: 50%;
    background: var(--gradient);
    color: #fff;
    display: flex;
    align-items: center;
    justify-content: center;
    box-shadow: 0 8px 25px -5px rgba(6, 182, 212, 0.5);
    opacity: 0;
    pointer-events: none;
    transform: translateY(20px);
    transition: all 0.35s;
    z-index: 99;
}
.to-top svg {
    width: 20px;
    height: 20px;
}
.to-top.show {
    opacity: 1;
    pointer-events: auto;
    transform: translateY(0);
}
.to-top:hover {
    transform: translateY(-4px);
}

/* 滚动动画 */
.reveal {
    opacity: 0;
    transform: translateY(40px);
    transition:
        opacity 0.8s ease-out,
        transform 0.8s ease-out;
}
.reveal.in-view {
    opacity: 1;
    transform: translateY(0);
}

/* 响应式 */
@media (max-width: 1024px) {
    .about-grid,
    .contact-wrap,
    .footer-inner {
        grid-template-columns: 1fr;
        gap: 60px;
    }
    .process-grid {
        grid-template-columns: 1fr 1fr;
        gap: 20px;
    }
    .step-arrow {
        display: none;
    }
    .product-grid,
    .adv-grid,
    .app-grid {
        grid-template-columns: repeat(2, 1fr);
    }
}

@media (max-width: 768px) {
    :root {
        --nav-h: 64px;
    }
    .container {
        padding: 0 20px;
    }
    .section {
        padding: 80px 0;
    }
    .section-head {
        margin-bottom: 48px;
    }
    .nav-menu {
        position: fixed;
        top: var(--nav-h);
        left: 0;
        right: 0;
        flex-direction: column;
        background: rgba(10, 31, 29, 0.98);
        backdrop-filter: blur(20px);
        padding: 24px;
        gap: 4px;
        border-bottom: 1px solid var(--c-border);
        transform: translateY(-150%);
        transition: transform 0.4s;
    }
    .nav-menu.open {
        transform: translateY(0);
    }
    .nav-link {
        width: 100%;
        padding: 14px 20px;
        text-align: center;
    }
    .menu-toggle {
        display: flex;
    }
    .hero-stats {
        gap: 32px;
    }
    .stat-num {
        font-size: 40px;
    }
    .stat-plus {
        font-size: 24px;
    }
    .process-grid {
        grid-template-columns: 1fr;
    }
    .product-grid,
    .adv-grid,
    .app-grid {
        grid-template-columns: 1fr;
    }
    .form-row {
        grid-template-columns: 1fr;
    }
    .contact-form {
        padding: 28px 20px;
    }
    .footer-cols {
        grid-template-columns: 1fr 1fr;
        gap: 28px;
    }
    .hero-cta {
        flex-direction: column;
        align-items: stretch;
    }
    .btn {
        justify-content: center;
    }
    .lang-toggle span {
        display: none;
    }
    .to-top {
        width: 42px;
        height: 42px;
        bottom: 20px;
        right: 20px;
    }
}

@media (max-width: 480px) {
    .hero-title {
        font-size: 36px;
    }
    .footer-cols {
        grid-template-columns: 1fr;
    }
    .footer-bottom .container {
        flex-direction: column;
        text-align: center;
    }
}

/* ============================================
   Our Grades 等级介绍
   ============================================ */

/* ============================================
   Contact 区域补充
   ============================================ */
.contact-sub {
    color: var(--c-text-soft);
    margin-bottom: 36px;
    line-height: 1.7;
    font-size: 16px;
}
.form-hint {
    display: block;
    margin-top: 6px;
    font-size: 12.5px;
    color: var(--c-text-muted);
    line-height: 1.5;
}

/* ============================================
   Footer 补充
   ============================================ */
.footer-col span {
    color: var(--c-text-soft);
    font-size: 14px;
    padding: 4px 0;
}
.footer-col a {
    color: var(--c-text-soft);
    font-size: 14px;
    padding: 4px 0;
    transition: color 0.2s;
}
.footer-col a:hover {
    color: var(--c-accent);
}
.footer-legal {
    color: var(--c-text-soft);
    font-size: 13.5px;
}
.footer-legal a {
    color: var(--c-text-soft);
    text-decoration: none;
    transition: color 0.2s;
}
.footer-legal a:hover {
    color: var(--c-accent);
}
.footer-bottom .container {
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-wrap: wrap;
    gap: 12px;
    padding-top: 24px;
    padding-bottom: 24px;
    border-top: 1px solid var(--c-border);
    font-size: 13.5px;
    color: var(--c-text-muted);
}

/* 装饰小工具 */
.footer-bottom span[data-i18n] {
    color: var(--c-text-muted);
}