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

:root {
    --glass-bg: rgba(255, 255, 255, 0.72);
    --glass-bg-hover: rgba(255, 255, 255, 0.85);
    --glass-border: rgba(255, 255, 255, 0.5);
    --glass-border-hover: rgba(255, 255, 255, 0.8);
    --glass-shadow: 0 8px 32px rgba(0, 0, 0, 0.04), 0 2px 8px rgba(0, 0, 0, 0.03);
    --glass-shadow-hover: 0 12px 40px rgba(0, 0, 0, 0.07), 0 4px 12px rgba(0, 0, 0, 0.04);

    --color-bg: #f0f2f5;
    --color-surface: #ffffff;
    --color-primary: #0071e3;
    --color-primary-hover: #0077ed;
    --color-accent: #5e5ce6;
    --color-text: #1d1d1f;
    --color-text-secondary: #86868b;
    --color-text-tertiary: #6e6e73;

    --radius-sm: 12px;
    --radius: 18px;
    --radius-lg: 24px;
    --radius-xl: 28px;

    --blur-amount: 20px;
    --saturate-amount: 180%;

    --max-width: 1100px;
}

html {
    font-size: 16px;
    scroll-behavior: smooth;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, "SF Pro Display", "SF Pro Text", "Helvetica Neue", "PingFang SC", "Microsoft YaHei", sans-serif;
    background: var(--color-bg);
    color: var(--color-text);
    line-height: 1.6;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    letter-spacing: -0.01em;
}

/* Subtle background glow orbs */
body::before {
    content: "";
    position: fixed;
    top: -30%;
    left: -20%;
    width: 70%;
    height: 70%;
    background: radial-gradient(ellipse at center, rgba(0, 113, 227, 0.06) 0%, transparent 70%);
    pointer-events: none;
    z-index: -1;
}

body::after {
    content: "";
    position: fixed;
    bottom: -20%;
    right: -15%;
    width: 60%;
    height: 60%;
    background: radial-gradient(ellipse at center, rgba(94, 92, 230, 0.05) 0%, transparent 70%);
    pointer-events: none;
    z-index: -1;
}

.container {
    margin: 0 auto;
    padding: 0 28px;
}

a {
    color: var(--color-primary);
    text-decoration: none;
    transition: color 0.3s ease;
}

a:hover {
    color: var(--color-primary-hover);
}

/* ===== Navbar — Frosted Glass ===== */
.navbar {
    position: sticky;
    top: 0;
    z-index: 100;
    width: 100%;
}

.nav-inner {
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 52px;
    padding: 0 28px;
    width: 100%;
    background: var(--glass-bg);
    backdrop-filter: blur(var(--blur-amount)) saturate(var(--saturate-amount));
    -webkit-backdrop-filter: blur(var(--blur-amount)) saturate(var(--saturate-amount));
    border-bottom: 1px solid var(--glass-border);
    box-shadow: var(--glass-shadow);
}

.nav-brand {
    font-size: 1.3rem;
    font-weight: 700;
    color: var(--color-text);
    letter-spacing: -0.5px;
}

.nav-brand:hover {
    color: var(--color-primary);
}

.nav-links {
    list-style: none;
    display: flex;
    gap: 8px;
}

.nav-links a {
    color: var(--color-text-secondary);
    font-weight: 500;
    font-size: 0.9rem;
    padding: 8px 18px;
    border-radius: 20px;
    transition: all 0.3s ease;
}

.nav-links a:hover {
    color: var(--color-text);
    background: rgba(0, 0, 0, 0.04);
}

.nav-links a.active {
    color: #fff;
    background: var(--color-primary);
}

/* ===== Hero ===== */
.hero {
    padding: 80px 0 60px;
    text-align: center;
}

.hero-name {
    font-size: 3.4rem;
    font-weight: 700;
    color: var(--color-text);
    letter-spacing: -1.5px;
    margin-bottom: 16px;
    line-height: 1.15;
}

.hero-tagline {
    font-size: 1.3rem;
    font-weight: 500;
    background: linear-gradient(135deg, var(--color-primary), var(--color-accent));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    margin-bottom: 24px;
}

.hero-desc {
    font-size: 1.05rem;
    color: var(--color-text-secondary);
    max-width: 560px;
    margin: 0 auto 40px;
}

.hero-actions {
    display: flex;
    gap: 16px;
    justify-content: center;
    flex-wrap: wrap;
}

/* ===== Glass Card ===== */
.glass-card {
    background: var(--glass-bg);
    backdrop-filter: blur(var(--blur-amount)) saturate(var(--saturate-amount));
    -webkit-backdrop-filter: blur(var(--blur-amount)) saturate(var(--saturate-amount));
    border: 1px solid var(--glass-border);
    border-radius: var(--radius-lg);
    box-shadow: var(--glass-shadow);
    transition: all 0.4s cubic-bezier(0.25, 0.1, 0.25, 1);
}

.glass-card:hover {
    background: var(--glass-bg-hover);
    border-color: var(--glass-border-hover);
    box-shadow: var(--glass-shadow-hover);
    transform: translateY(-2px);
}

/* ===== Buttons ===== */
.btn {
    display: inline-block;
    padding: 13px 30px;
    border-radius: 24px;
    font-weight: 600;
    font-size: 0.95rem;
    transition: all 0.3s cubic-bezier(0.25, 0.1, 0.25, 1);
    cursor: pointer;
    border: none;
    letter-spacing: -0.01em;
}

.btn-primary {
    background: var(--color-primary);
    color: #fff;
    box-shadow: 0 4px 14px rgba(0, 113, 227, 0.3);
}

.btn-primary:hover {
    background: var(--color-primary-hover);
    color: #fff;
    transform: translateY(-1px);
    box-shadow: 0 8px 22px rgba(0, 113, 227, 0.4);
}

/* ===== Sections ===== */
.section {
    padding: 72px 0;
}

.section-alt {
    position: relative;
}

.section-alt::before {
    content: "";
    position: absolute;
    inset: 0;
    background: rgba(255, 255, 255, 0.4);
    backdrop-filter: blur(30px);
    -webkit-backdrop-filter: blur(30px);
    z-index: -1;
}

.section-title {
    font-size: 1.8rem;
    font-weight: 700;
    text-align: center;
    margin-bottom: 48px;
    color: var(--color-text);
    letter-spacing: -0.5px;
}

/* ===== Page Header ===== */
.page-header {
    padding: 64px 0 20px;
    text-align: center;
}

.page-header h1 {
    font-size: 2.4rem;
    font-weight: 700;
    letter-spacing: -1px;
}

/* ===== Cards Grid ===== */
.card-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 24px;
}

.card {
    background: var(--glass-bg);
    backdrop-filter: blur(var(--blur-amount)) saturate(var(--saturate-amount));
    -webkit-backdrop-filter: blur(var(--blur-amount)) saturate(var(--saturate-amount));
    border: 1px solid var(--glass-border);
    border-radius: var(--radius-lg);
    padding: 36px 32px;
    text-align: center;
    box-shadow: var(--glass-shadow);
    transition: all 0.4s cubic-bezier(0.25, 0.1, 0.25, 1);
}

.card:hover {
    background: var(--glass-bg-hover);
    border-color: var(--glass-border-hover);
    box-shadow: var(--glass-shadow-hover);
    transform: translateY(-3px);
}

.card-icon {
    font-size: 2.6rem;
    margin-bottom: 20px;
}

.card h3 {
    font-size: 1.15rem;
    font-weight: 600;
    margin-bottom: 10px;
    color: var(--color-text);
    letter-spacing: -0.02em;
}

.card p {
    font-size: 0.95rem;
    color: var(--color-text-secondary);
    line-height: 1.6;
}

/* ===== About Page ===== */
.about-content {
    max-width: 680px;
    margin: 0 auto;
    font-size: 1.05rem;
    color: var(--color-text-secondary);
    line-height: 1.8;
}

.about-content p {
    margin-bottom: 24px;
}

.about-content strong {
    color: var(--color-text);
    font-weight: 600;
}

/* ===== Skills ===== */
.skills-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
    gap: 24px;
    max-width: 920px;
    margin: 0 auto;
}

.skill-group {
    background: var(--glass-bg);
    backdrop-filter: blur(var(--blur-amount)) saturate(var(--saturate-amount));
    -webkit-backdrop-filter: blur(var(--blur-amount)) saturate(var(--saturate-amount));
    border: 1px solid var(--glass-border);
    border-radius: var(--radius);
    padding: 28px 24px;
    box-shadow: var(--glass-shadow);
    transition: all 0.3s ease;
}

.skill-group:hover {
    background: var(--glass-bg-hover);
    border-color: var(--glass-border-hover);
    box-shadow: var(--glass-shadow-hover);
    transform: translateY(-2px);
}

.skill-group h3 {
    font-size: 0.85rem;
    font-weight: 700;
    color: var(--color-primary);
    text-transform: uppercase;
    letter-spacing: 1.5px;
    margin-bottom: 16px;
}

.skill-group ul {
    list-style: none;
}

.skill-group li {
    padding: 7px 0;
    color: var(--color-text-secondary);
    font-size: 0.95rem;
    position: relative;
    padding-left: 22px;
}

.skill-group li::before {
    content: "";
    position: absolute;
    left: 0;
    top: 50%;
    transform: translateY(-50%);
    width: 7px;
    height: 7px;
    background: linear-gradient(135deg, var(--color-primary), var(--color-accent));
    border-radius: 50%;
}

/* ===== Footer ===== */
.footer {
    margin-top: auto;
    padding: 28px 0;
    text-align: center;
}

.footer .container {
    background: var(--glass-bg);
    backdrop-filter: blur(var(--blur-amount)) saturate(var(--saturate-amount));
    -webkit-backdrop-filter: blur(var(--blur-amount)) saturate(var(--saturate-amount));
    border: 1px solid var(--glass-border);
    border-radius: var(--radius);
    padding: 20px 28px;
    display: inline-block;
    box-shadow: var(--glass-shadow);
}

.footer p {
    font-size: 0.85rem;
    color: var(--color-text-tertiary);
}

.footer .icp {
    margin-top: 6px;
}

.footer .icp a {
    color: var(--color-text-tertiary);
    font-size: 0.8rem;
}

.footer .icp a:hover {
    color: var(--color-primary);
}

/* ===== Responsive ===== */
@media (max-width: 768px) {
    .hero {
        padding: 50px 0 40px;
    }

    .hero-name {
        font-size: 2.4rem;
    }

    .hero-tagline {
        font-size: 1.1rem;
    }

    .hero-desc {
        font-size: 0.95rem;
    }

    .section {
        padding: 48px 0;
    }

    .section-title {
        font-size: 1.5rem;
        margin-bottom: 32px;
    }

    .card-grid {
        grid-template-columns: 1fr;
    }

    .card {
        padding: 28px 24px;
    }

    .skills-grid {
        grid-template-columns: 1fr 1fr;
        gap: 16px;
    }

    .skill-group {
        padding: 20px 18px;
    }

    .nav-inner {
        height: 48px;
        padding: 0 18px;
    }

    .nav-links a {
        padding: 6px 14px;
        font-size: 0.85rem;
    }


}

@media (max-width: 480px) {
    .hero-name {
        font-size: 1.9rem;
    }

    .skills-grid {
        grid-template-columns: 1fr;
    }

    .page-header h1 {
        font-size: 1.8rem;
    }

    .section-title {
        font-size: 1.35rem;
    }
}