/* ============================================
   深算AI - 官网样式
   设计参考: Linear / Stripe / Vercel
   ============================================ */

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

:root {
    --bg:        #09090b;
    --bg-subtle: #0f0f14;
    --surface:   #15151a;
    --surface-2: #1c1c24;
    --border:    rgba(255,255,255,0.06);
    --border-h:  rgba(255,255,255,0.12);

    --text-1:    #fafafa;
    --text-2:    #a1a1aa;
    --text-3:    #52525b;

    --accent:    #818cf8;
    --accent-2:  #a78bfa;
    --accent-3:  #c084fc;
    --accent-glow: rgba(129,140,248,0.15);

    --radius:    12px;
    --radius-lg: 20px;

    --font: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', 'PingFang SC',
            'Hiragino Sans GB', 'Microsoft YaHei', sans-serif;
}

html {
    scroll-behavior: smooth;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

body {
    font-family: var(--font);
    background: var(--bg);
    color: var(--text-1);
    line-height: 1.6;
    overflow-x: hidden;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 1.5rem;
}

/* --- Skip link --- */
.skip-link {
    position: absolute;
    top: -100%;
    left: 1rem;
    background: var(--accent);
    color: #fff;
    padding: 0.5rem 1rem;
    border-radius: 6px;
    z-index: 10000;
    text-decoration: none;
}
.skip-link:focus { top: 1rem; }

/* ========== NAV ========== */
.navbar {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 1000;
    background: rgba(9,9,11,0.6);
    backdrop-filter: blur(20px) saturate(1.4);
    -webkit-backdrop-filter: blur(20px) saturate(1.4);
    border-bottom: 1px solid var(--border);
}

.nav-inner {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 1.5rem;
    display: flex;
    align-items: center;
    height: 64px;
}

.nav-brand {
    display: flex;
    align-items: center;
    gap: 0.6rem;
    text-decoration: none;
    color: var(--text-1);
    font-weight: 700;
    font-size: 1.15rem;
    letter-spacing: -0.02em;
}

.nav-logo { flex-shrink: 0; }

.nav-menu {
    display: flex;
    list-style: none;
    gap: 0.25rem;
    margin-left: auto;
}

.nav-menu a {
    color: var(--text-2);
    text-decoration: none;
    font-size: 0.875rem;
    font-weight: 500;
    padding: 0.5rem 0.875rem;
    border-radius: 8px;
    transition: color 0.2s, background 0.2s;
}

.nav-menu a:hover {
    color: var(--text-1);
    background: rgba(255,255,255,0.05);
}

.nav-cta {
    margin-left: 1.5rem;
    padding: 0.5rem 1.125rem;
    font-size: 0.8125rem;
    font-weight: 600;
    color: #fff;
    background: var(--accent);
    border-radius: 8px;
    text-decoration: none;
    transition: background 0.2s, transform 0.15s;
}
.nav-cta:hover {
    background: var(--accent-2);
    transform: translateY(-1px);
}

.nav-toggle {
    display: none;
    flex-direction: column;
    gap: 5px;
    background: none;
    border: none;
    cursor: pointer;
    padding: 6px;
    margin-left: auto;
}
.nav-toggle span {
    display: block;
    width: 20px;
    height: 2px;
    background: var(--text-2);
    border-radius: 2px;
    transition: 0.3s;
}

/* ========== HERO ========== */
.hero {
    position: relative;
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    overflow: hidden;
    padding: 120px 1.5rem 80px;
}

.hero-glow {
    position: absolute;
    top: -20%;
    left: 50%;
    transform: translateX(-50%);
    width: 800px;
    height: 600px;
    background: radial-gradient(ellipse at center,
        rgba(129,140,248,0.18) 0%,
        rgba(167,139,250,0.08) 40%,
        transparent 70%);
    pointer-events: none;
    animation: glowPulse 8s ease-in-out infinite alternate;
}

@keyframes glowPulse {
    0%   { opacity: 0.8; transform: translateX(-50%) scale(1); }
    100% { opacity: 1;   transform: translateX(-50%) scale(1.1); }
}

.hero-grid {
    position: absolute;
    inset: 0;
    background-image:
        linear-gradient(rgba(255,255,255,0.02) 1px, transparent 1px),
        linear-gradient(90deg, rgba(255,255,255,0.02) 1px, transparent 1px);
    background-size: 60px 60px;
    mask-image: radial-gradient(ellipse at center, black 30%, transparent 70%);
    -webkit-mask-image: radial-gradient(ellipse at center, black 30%, transparent 70%);
    pointer-events: none;
}

.hero-content {
    position: relative;
    z-index: 1;
    text-align: center;
    max-width: 820px;
}

.hero-badge {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.375rem 1rem 0.375rem 0.625rem;
    background: rgba(129,140,248,0.08);
    border: 1px solid rgba(129,140,248,0.15);
    border-radius: 100px;
    font-size: 0.8125rem;
    font-weight: 500;
    color: var(--accent);
    margin-bottom: 2rem;
    animation: fadeUp 0.8s ease both;
}

.badge-dot {
    width: 6px;
    height: 6px;
    background: var(--accent);
    border-radius: 50%;
    animation: dotPulse 2s ease-in-out infinite;
}

@keyframes dotPulse {
    0%, 100% { opacity: 1; box-shadow: 0 0 0 0 rgba(129,140,248,0.5); }
    50%      { opacity: 0.7; box-shadow: 0 0 0 6px rgba(129,140,248,0); }
}

.hero-title {
    font-size: clamp(2.5rem, 6vw, 4.5rem);
    font-weight: 800;
    line-height: 1.1;
    letter-spacing: -0.04em;
    color: var(--text-1);
    margin-bottom: 1.5rem;
    animation: fadeUp 0.8s ease 0.1s both;
}

.gradient-text {
    background: linear-gradient(135deg, var(--accent), var(--accent-2), var(--accent-3));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.hero-desc {
    font-size: 1.125rem;
    color: var(--text-2);
    line-height: 1.75;
    margin-bottom: 2.5rem;
    animation: fadeUp 0.8s ease 0.2s both;
}

.hero-actions {
    display: flex;
    gap: 0.75rem;
    justify-content: center;
    margin-bottom: 4rem;
    animation: fadeUp 0.8s ease 0.3s both;
}

/* --- Buttons --- */
.btn {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.75rem 1.5rem;
    font-size: 0.9375rem;
    font-weight: 600;
    font-family: var(--font);
    border-radius: 10px;
    text-decoration: none;
    transition: all 0.2s ease;
    border: none;
    cursor: pointer;
}

.btn-primary {
    background: var(--accent);
    color: #fff;
    box-shadow: 0 0 20px rgba(129,140,248,0.3), inset 0 1px 0 rgba(255,255,255,0.1);
}
.btn-primary:hover {
    background: var(--accent-2);
    box-shadow: 0 0 30px rgba(129,140,248,0.5), inset 0 1px 0 rgba(255,255,255,0.15);
    transform: translateY(-2px);
}

.btn-ghost {
    background: rgba(255,255,255,0.04);
    color: var(--text-2);
    border: 1px solid var(--border-h);
}
.btn-ghost:hover {
    background: rgba(255,255,255,0.08);
    color: var(--text-1);
    border-color: rgba(255,255,255,0.2);
}

/* Hero Stats */
.hero-stats {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 2.5rem;
    animation: fadeUp 0.8s ease 0.4s both;
}

.stat { text-align: center; }

.stat-num {
    display: block;
    font-size: 1.5rem;
    font-weight: 800;
    letter-spacing: -0.03em;
    color: var(--text-1);
}

.stat-label {
    font-size: 0.8125rem;
    color: var(--text-3);
    font-weight: 500;
}

.stat-divider {
    width: 1px;
    height: 32px;
    background: var(--border-h);
}

/* ========== PRODUCTS ========== */
.products {
    padding: 8rem 0;
    position: relative;
    overflow: hidden;
}

/* 右上方慢速漂移光球 */
.products::before {
    content: '';
    position: absolute;
    top: -10%;
    right: -8%;
    width: 500px;
    height: 500px;
    border-radius: 50%;
    background: radial-gradient(circle, rgba(129,140,248,0.06) 0%, transparent 70%);
    animation: driftA 20s ease-in-out infinite;
    pointer-events: none;
}

/* 左下方慢速漂移光球 */
.products::after {
    content: '';
    position: absolute;
    bottom: -15%;
    left: -5%;
    width: 400px;
    height: 400px;
    border-radius: 50%;
    background: radial-gradient(circle, rgba(192,132,252,0.05) 0%, transparent 70%);
    animation: driftB 25s ease-in-out infinite;
    pointer-events: none;
}

.section-header {
    text-align: center;
    margin-bottom: 4rem;
}

.section-tag {
    display: inline-block;
    font-size: 0.75rem;
    font-weight: 700;
    letter-spacing: 0.12em;
    color: var(--accent);
    background: rgba(129,140,248,0.08);
    padding: 0.3rem 0.875rem;
    border-radius: 100px;
    margin-bottom: 1rem;
}

.section-title {
    font-size: clamp(2rem, 4vw, 2.75rem);
    font-weight: 800;
    letter-spacing: -0.03em;
    color: var(--text-1);
    margin-bottom: 1rem;
    text-align: center;
}

.section-desc {
    font-size: 1.0625rem;
    color: var(--text-2);
    line-height: 1.7;
}

/* Product grid */
.product-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 1.25rem;
}

.product-card {
    position: relative;
    display: flex;
    flex-direction: column;
    padding: 1.75rem;
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: var(--radius-lg);
    text-decoration: none;
    color: inherit;
    transition: border-color 0.3s, transform 0.3s, box-shadow 0.3s;
    overflow: hidden;
}

.product-card .card-glow {
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 100%;
    background: radial-gradient(ellipse at 50% 0%, var(--accent-glow), transparent 60%);
    opacity: 0;
    transition: opacity 0.4s;
    pointer-events: none;
}

.product-card:hover {
    border-color: rgba(129,140,248,0.25);
    transform: translateY(-4px);
    box-shadow: 0 16px 48px rgba(0,0,0,0.35);
}

.product-card:hover .card-glow {
    opacity: 1;
}

.card-featured {
    grid-column: span 2;
}

.card-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    margin-bottom: 1.25rem;
    position: relative;
    z-index: 1;
}

.card-icon {
    width: 44px;
    height: 44px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: rgba(129,140,248,0.1);
    border: 1px solid rgba(129,140,248,0.15);
    border-radius: 12px;
    color: var(--accent);
}

.card-status {
    padding: 0.25rem 0.75rem;
    border-radius: 100px;
    font-size: 0.6875rem;
    font-weight: 600;
    letter-spacing: 0.02em;
}

.card-status.active {
    background: rgba(52,211,153,0.1);
    color: #34d399;
    border: 1px solid rgba(52,211,153,0.2);
}

.product-card h3 {
    font-size: 1.25rem;
    font-weight: 700;
    margin-bottom: 0.625rem;
    letter-spacing: -0.01em;
    position: relative;
    z-index: 1;
}

.product-card p {
    font-size: 0.9rem;
    color: var(--text-2);
    line-height: 1.65;
    margin-bottom: 1.25rem;
    flex-grow: 1;
    position: relative;
    z-index: 1;
}

.card-tags {
    display: flex;
    flex-wrap: wrap;
    gap: 0.375rem;
    margin-bottom: 1.25rem;
    position: relative;
    z-index: 1;
}

.card-tags span {
    padding: 0.25rem 0.625rem;
    background: rgba(255,255,255,0.04);
    border: 1px solid var(--border);
    border-radius: 6px;
    font-size: 0.75rem;
    color: var(--text-3);
    font-weight: 500;
}

.card-link {
    display: inline-flex;
    align-items: center;
    gap: 0.375rem;
    font-size: 0.875rem;
    font-weight: 600;
    color: var(--accent);
    background: none;
    padding: 0;
    position: relative;
    z-index: 1;
    transition: gap 0.25s, color 0.25s;
    letter-spacing: 0.01em;
}

.product-card:hover .card-link {
    color: var(--accent-2);
    gap: 0.625rem;
}

/* ========== ABOUT ========== */
.about {
    padding: 8rem 0;
    background: var(--bg-subtle);
    border-top: 1px solid var(--border);
    border-bottom: 1px solid var(--border);
    position: relative;
    overflow: hidden;
}

/* 水平扫光线 */
.about::before {
    content: '';
    position: absolute;
    top: 50%;
    left: -100%;
    width: 60%;
    height: 1px;
    background: linear-gradient(90deg, transparent, rgba(129,140,248,0.15), rgba(167,139,250,0.08), transparent);
    animation: scanLine 12s linear infinite;
    pointer-events: none;
}

/* 中央微弱脉冲 */
.about::after {
    content: '';
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    width: 600px;
    height: 400px;
    border-radius: 50%;
    background: radial-gradient(ellipse, rgba(129,140,248,0.04) 0%, transparent 60%);
    animation: gentlePulse 8s ease-in-out infinite;
    pointer-events: none;
}

.values-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 1.25rem;
}

.value-card {
    padding: 2rem;
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: var(--radius-lg);
    transition: border-color 0.3s, transform 0.3s;
}

.value-card:hover {
    border-color: var(--border-h);
    transform: translateY(-2px);
}

.value-icon {
    width: 44px;
    height: 44px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: rgba(129,140,248,0.08);
    border: 1px solid rgba(129,140,248,0.12);
    border-radius: 12px;
    color: var(--accent);
    margin-bottom: 1.25rem;
}

.value-card h4 {
    font-size: 1.125rem;
    font-weight: 700;
    margin-bottom: 0.5rem;
    letter-spacing: -0.01em;
}

.value-card p {
    font-size: 0.9rem;
    color: var(--text-2);
    line-height: 1.65;
}

/* ========== CONTACT ========== */
.contact {
    padding: 8rem 0;
    position: relative;
    overflow: hidden;
}

/* 底部渐变极光带 */
.contact::before {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    right: 0;
    height: 200px;
    background: linear-gradient(180deg,
        transparent 0%,
        rgba(129,140,248,0.03) 40%,
        rgba(192,132,252,0.05) 100%
    );
    pointer-events: none;
}

/* 右侧装饰弧线 */
.contact::after {
    content: '';
    position: absolute;
    top: 20%;
    right: -200px;
    width: 500px;
    height: 500px;
    border-radius: 50%;
    border: 1px solid rgba(129,140,248,0.06);
    animation: orbitSlow 30s linear infinite;
    pointer-events: none;
}

.contact-inner {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 4rem;
}

.contact-text {
    flex: 1;
}

.contact-text p {
    font-size: 1.0625rem;
    color: var(--text-2);
    line-height: 1.7;
    margin-top: 1rem;
}

/* ── Glass panel with animated gradient border ── */
.contact-panel {
    position: relative;
    flex-shrink: 0;
    width: 400px;
    border-radius: 20px;
    padding: 1px;
    background: linear-gradient(
        135deg,
        rgba(129,140,248,0.4) 0%,
        rgba(167,139,250,0.15) 25%,
        rgba(255,255,255,0.06) 50%,
        rgba(192,132,252,0.15) 75%,
        rgba(129,140,248,0.4) 100%
    );
    background-size: 300% 300%;
    animation: borderShift 6s ease-in-out infinite;
}

@keyframes borderShift {
    0%   { background-position: 0% 50%; }
    50%  { background-position: 100% 50%; }
    100% { background-position: 0% 50%; }
}

.contact-panel-inner {
    position: relative;
    background: linear-gradient(160deg, #111118 0%, #0c0c12 100%);
    border-radius: 19px;
    padding: 2rem 2rem;
    overflow: hidden;
}

/* ── Ambient glow inside card ── */
.contact-panel-glow {
    position: absolute;
    top: -40%;
    right: -20%;
    width: 240px;
    height: 240px;
    background: radial-gradient(circle, rgba(129,140,248,0.12) 0%, transparent 70%);
    pointer-events: none;
}

/* ── Info rows ── */
.contact-row {
    display: flex;
    align-items: center;
    gap: 1rem;
    position: relative;
    z-index: 1;
}

.contact-dot {
    width: 10px;
    height: 10px;
    border-radius: 50%;
    background: var(--accent);
    box-shadow: 0 0 8px rgba(129,140,248,0.5);
    flex-shrink: 0;
}

.contact-dot.dot-mail {
    background: var(--accent-3);
    box-shadow: 0 0 8px rgba(192,132,252,0.5);
}

.contact-info {
    display: flex;
    flex-direction: column;
    gap: 0.15rem;
}

.contact-label {
    font-size: 0.6875rem;
    font-weight: 600;
    letter-spacing: 0.1em;
    text-transform: uppercase;
    color: var(--text-3);
}

.contact-value {
    font-size: 1.0625rem;
    font-weight: 600;
    color: var(--text-1);
    letter-spacing: -0.01em;
}

/* ── Divider ── */
.contact-divider {
    height: 1px;
    margin: 1.25rem 0;
    background: linear-gradient(90deg,
        transparent 0%,
        rgba(255,255,255,0.08) 20%,
        rgba(129,140,248,0.12) 50%,
        rgba(255,255,255,0.08) 80%,
        transparent 100%
    );
    position: relative;
    z-index: 1;
}

/* ── Email link ── */
.contact-email {
    text-decoration: none;
    color: var(--accent);
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    transition: color 0.25s, gap 0.25s;
}

.contact-email svg {
    opacity: 0.7;
    transform: translateX(0);
    transition: opacity 0.25s, transform 0.25s;
    color: var(--accent);
}

.contact-email:hover {
    color: var(--accent-3);
    gap: 0.75rem;
}

.contact-email:hover svg {
    opacity: 1;
    transform: translateX(3px);
    color: var(--accent-3);
}

/* ========== FOOTER ========== */
.footer {
    border-top: 1px solid var(--border);
    padding: 3rem 0 2rem;
}

.footer-inner {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding-bottom: 2rem;
    border-bottom: 1px solid var(--border);
}

.footer-logo {
    font-weight: 700;
    font-size: 1.125rem;
    background: linear-gradient(135deg, var(--accent), var(--accent-3));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.footer-brand p {
    font-size: 0.8125rem;
    color: var(--text-3);
    margin-top: 0.25rem;
}

.footer-links {
    display: flex;
    gap: 1.5rem;
}

.footer-links a {
    color: var(--text-3);
    text-decoration: none;
    font-size: 0.8125rem;
    transition: color 0.2s;
}

.footer-links a:hover {
    color: var(--text-2);
}

.footer-bottom {
    padding-top: 1.5rem;
    text-align: center;
}

.footer-bottom p {
    font-size: 0.8125rem;
    color: var(--text-3);
}

/* ========== ANIMATIONS ========== */
@keyframes fadeUp {
    from {
        opacity: 0;
        transform: translateY(24px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

/* ── 背景装饰动画 ── */
@keyframes driftA {
    0%, 100% { transform: translate(0, 0); }
    33%      { transform: translate(-30px, 20px); }
    66%      { transform: translate(15px, -15px); }
}

@keyframes driftB {
    0%, 100% { transform: translate(0, 0); }
    40%      { transform: translate(20px, -25px); }
    70%      { transform: translate(-15px, 10px); }
}

@keyframes scanLine {
    0%   { left: -60%; }
    100% { left: 160%; }
}

@keyframes gentlePulse {
    0%, 100% { opacity: 0.5; transform: translate(-50%, -50%) scale(1); }
    50%      { opacity: 1;   transform: translate(-50%, -50%) scale(1.15); }
}

@keyframes orbitSlow {
    0%   { transform: rotate(0deg); }
    100% { transform: rotate(360deg); }
}

/* Reveal on scroll */
.reveal-item {
    opacity: 0;
    transform: translateY(24px);
    transition: opacity 0.6s ease, transform 0.6s ease;
}

.reveal-item.visible {
    opacity: 1;
    transform: translateY(0);
}

/* ========== SCROLLBAR ========== */
::-webkit-scrollbar {
    width: 8px;
}

::-webkit-scrollbar-track {
    background: var(--bg);
}

::-webkit-scrollbar-thumb {
    background: var(--surface-2);
    border-radius: 8px;
}

::-webkit-scrollbar-thumb:hover {
    background: var(--text-3);
}

/* ========== SELECTION ========== */
::selection {
    background: rgba(129,140,248,0.25);
    color: #fff;
}

/* 粒子动画 (from animations.js) */
.hero-bg {
    position: absolute;
    top: 0; left: 0; right: 0; bottom: 0;
    overflow: hidden;
    z-index: 0;
    pointer-events: none;
}

@keyframes float {
    0%, 100% { transform: translateY(0) translateX(0); opacity: 0.6; }
    25% { transform: translateY(-30px) translateX(10px); opacity: 1; }
    50% { transform: translateY(-20px) translateX(-10px); opacity: 0.8; }
    75% { transform: translateY(-40px) translateX(5px); opacity: 0.6; }
}

/* 鼠标视差图层 */
.parallax-layer {
    position: absolute;
    top: 0; left: 0; right: 0; bottom: 0;
    pointer-events: none;
    z-index: 0;
}

/* 滚动数字动画 */
.stat-number[data-target] {
    transition: all 0.3s ease;
}

/* 卡片3D倾斜 */
.product-card, .value-card {
    transform-style: preserve-3d;
    transition: transform 0.1s ease;
}