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

:root {
    --bg: #ffffff;
    --bg-secondary: #f5f5f7;
    --text: #1d1d1f;
    --text-secondary: #6e6e73;
    --accent: #0071e3;
    --accent-2: #a855f7;
    --accent-gradient: linear-gradient(135deg, #0071e3, #a855f7);
    --card-bg: rgba(0, 0, 0, 0.02);
    --card-border: rgba(0, 0, 0, 0.08);
    --nav-bg: rgba(255, 255, 255, 0.8);
    --nav-bg-scrolled: rgba(255, 255, 255, 0.95);
    --nav-border: rgba(0, 0, 0, 0.06);
    --mobile-bg: rgba(255, 255, 255, 0.98);
    --tag-bg: rgba(0, 0, 0, 0.04);
    --tag-border: rgba(0, 0, 0, 0.08);
    --pill-bg: rgba(0, 0, 0, 0.03);
    --pill-border: rgba(0, 0, 0, 0.1);
    --radius: 20px;
    --transition: 0.4s cubic-bezier(0.25, 0.46, 0.45, 0.94);
}

[data-theme="dark"] {
    --bg: #000000;
    --bg-secondary: #0a0a0a;
    --text: #f5f5f7;
    --text-secondary: #86868b;
    --accent: #2997ff;
    --accent-2: #bf5af2;
    --accent-gradient: linear-gradient(135deg, #2997ff, #bf5af2);
    --card-bg: rgba(255, 255, 255, 0.04);
    --card-border: rgba(255, 255, 255, 0.08);
    --nav-bg: rgba(0, 0, 0, 0.8);
    --nav-bg-scrolled: rgba(0, 0, 0, 0.95);
    --nav-border: rgba(255, 255, 255, 0.05);
    --mobile-bg: rgba(0, 0, 0, 0.98);
    --tag-bg: rgba(255, 255, 255, 0.06);
    --tag-border: rgba(255, 255, 255, 0.06);
    --pill-bg: rgba(255, 255, 255, 0.04);
    --pill-border: rgba(255, 255, 255, 0.1);
}

html { scroll-behavior: smooth; font-size: 16px; }

body {
    font-family: 'Inter', 'Noto Sans SC', -apple-system, sans-serif;
    background: var(--bg);
    color: var(--text);
    line-height: 1.7;
    overflow-x: hidden;
    -webkit-font-smoothing: antialiased;
}

.container { max-width: 1200px; margin: 0 auto; padding: 0 clamp(20px, 5vw, 80px); }

/* === NAVIGATION === */
.nav {
    position: fixed; top: 0; left: 0; right: 0; z-index: 1000;
    padding: 0 40px; height: 60px;
    background: var(--nav-bg);
    backdrop-filter: saturate(180%) blur(20px);
    -webkit-backdrop-filter: saturate(180%) blur(20px);
    border-bottom: 1px solid var(--nav-border);
    transition: var(--transition);
}

.nav.scrolled { background: var(--nav-bg-scrolled); }

.nav-inner {
    max-width: 1200px; margin: 0 auto;
    display: flex; align-items: center; justify-content: space-between;
    height: 100%;
}

.nav-logo {
    font-size: 1.2rem; font-weight: 800; letter-spacing: 2px;
    color: var(--text); text-decoration: none;
    background: var(--accent-gradient); -webkit-background-clip: text;
    -webkit-text-fill-color: transparent; background-clip: text;
}

.nav-links { display: flex; gap: 32px; }
.nav-links a {
    color: var(--text-secondary); text-decoration: none;
    font-size: 0.85rem; font-weight: 500; letter-spacing: 0.5px;
    transition: color 0.3s;
}
.nav-links a:hover { color: var(--text); }

.nav-toggle {
    display: none; background: none; border: none; cursor: pointer;
    width: 24px; height: 20px; position: relative;
}
.nav-toggle span {
    display: block; width: 100%; height: 2px; background: var(--text);
    position: absolute; left: 0; transition: 0.3s;
}
.nav-toggle span:nth-child(1) { top: 0; }
.nav-toggle span:nth-child(2) { top: 9px; }
.nav-toggle span:nth-child(3) { top: 18px; }
.nav-toggle.active span:nth-child(1) { transform: rotate(45deg); top: 9px; }
.nav-toggle.active span:nth-child(2) { opacity: 0; }
.nav-toggle.active span:nth-child(3) { transform: rotate(-45deg); top: 9px; }

.mobile-menu {
    display: none; position: fixed; top: 60px; left: 0; right: 0;
    background: var(--mobile-bg); z-index: 999;
    flex-direction: column; padding: 40px;
    backdrop-filter: blur(20px);
}
.mobile-menu.active { display: flex; }
.mobile-menu a {
    color: var(--text); text-decoration: none; font-size: 1.5rem;
    font-weight: 600; padding: 16px 0; border-bottom: 1px solid var(--card-border);
    transition: color 0.3s;
}

/* === HERO === */
.hero {
    min-height: 100vh; display: flex; align-items: center; justify-content: center;
    position: relative; overflow: hidden; padding: 120px 40px 80px;
}

.hero-bg { position: absolute; inset: 0; overflow: hidden; }

.gradient-orb {
    position: absolute; border-radius: 50%; filter: blur(120px); opacity: 0.15;
    animation: float 20s ease-in-out infinite; transition: opacity 0.6s;
}
[data-theme="dark"] .gradient-orb { opacity: 0.3; }
.orb-1 { width: 600px; height: 600px; background: #2997ff; top: -200px; right: -100px; }
.orb-2 { width: 500px; height: 500px; background: #bf5af2; bottom: -150px; left: -100px; animation-delay: -7s; }
.orb-3 { width: 400px; height: 400px; background: #30d158; top: 50%; left: 50%; transform: translate(-50%, -50%); animation-delay: -14s; }

@keyframes float {
    0%, 100% { transform: translate(0, 0) scale(1); }
    33% { transform: translate(30px, -30px) scale(1.05); }
    66% { transform: translate(-20px, 20px) scale(0.95); }
}

.hero-content { text-align: center; position: relative; z-index: 1; max-width: 900px; }

.hero-label {
    font-size: 0.8rem; letter-spacing: 4px; color: var(--accent);
    font-weight: 600; margin-bottom: 24px; text-transform: uppercase;
}

.hero-title {
    font-size: clamp(3rem, 8vw, 7rem); font-weight: 900;
    line-height: 1.05; letter-spacing: -2px; margin-bottom: 32px;
}
.hero-title .line { display: block; }

.gradient-text {
    background: var(--accent-gradient);
    -webkit-background-clip: text; -webkit-text-fill-color: transparent;
    background-clip: text;
}

.hero-subtitle {
    font-size: clamp(1rem, 2vw, 1.25rem); color: var(--text-secondary);
    font-weight: 400; line-height: 1.8; margin-bottom: 48px;
}

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

/* === BUTTONS === */
.btn {
    display: inline-flex; align-items: center; padding: 14px 32px;
    border-radius: 980px; font-size: 0.95rem; font-weight: 600;
    text-decoration: none; transition: var(--transition); cursor: pointer;
    letter-spacing: 0.3px;
}
.btn-primary {
    background: var(--accent); color: #fff; border: none;
}
.btn-primary:hover { background: #0077ed; transform: scale(1.05); }
.btn-ghost {
    background: transparent; color: var(--accent);
    border: 1.5px solid rgba(41, 151, 255, 0.4);
}
.btn-ghost:hover { border-color: var(--accent); background: rgba(41, 151, 255, 0.08); }

/* === SCROLL INDICATOR === */
.scroll-indicator {
    position: absolute; bottom: 40px; left: 50%; transform: translateX(-50%);
    display: flex; flex-direction: column; align-items: center; gap: 12px;
}
.scroll-indicator span { font-size: 0.7rem; letter-spacing: 3px; color: var(--text-secondary); text-transform: uppercase; }
.scroll-line {
    width: 1px; height: 60px; background: linear-gradient(to bottom, var(--accent), transparent);
    animation: scrollPulse 2s ease-in-out infinite;
}
@keyframes scrollPulse {
    0%, 100% { opacity: 0.3; transform: scaleY(0.6); }
    50% { opacity: 1; transform: scaleY(1); }
}

/* === SECTIONS === */
.section { padding: clamp(80px, 12vw, 160px) 0; position: relative; }
.section:nth-child(even) { background: var(--bg-secondary); }

.section-header { text-align: center; margin-bottom: clamp(48px, 6vw, 80px); }
.section-label {
    font-size: 0.75rem; letter-spacing: 4px; color: var(--accent);
    font-weight: 600; margin-bottom: 16px; text-transform: uppercase;
}
.section-title {
    font-size: clamp(2rem, 5vw, 3.5rem); font-weight: 800;
    letter-spacing: -1px; line-height: 1.2;
}
.section-desc {
    font-size: 1.1rem; color: var(--text-secondary); margin-top: 16px;
    max-width: 600px; margin-left: auto; margin-right: auto;
}

/* === ABOUT === */
.about-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 60px; align-items: start; }
.about-text p { color: var(--text-secondary); margin-bottom: 20px; font-size: 1.05rem; }
.about-lead { font-size: 1.3rem !important; color: var(--text) !important; font-weight: 500; line-height: 1.6; }
.about-stats { display: grid; grid-template-columns: 1fr 1fr; gap: 20px; }
.stat-card {
    background: var(--card-bg); border: 1px solid var(--card-border);
    border-radius: var(--radius); padding: 32px 24px; text-align: center;
    transition: var(--transition);
}
.stat-card:hover { border-color: rgba(41, 151, 255, 0.3); transform: translateY(-4px); }
.stat-number { font-size: 2.5rem; font-weight: 800; display: inline; background: var(--accent-gradient); -webkit-background-clip: text; -webkit-text-fill-color: transparent; background-clip: text; }
.stat-suffix { font-size: 2rem; font-weight: 700; background: var(--accent-gradient); -webkit-background-clip: text; -webkit-text-fill-color: transparent; background-clip: text; }
.stat-label { display: block; font-size: 0.85rem; color: var(--text-secondary); margin-top: 8px; }

/* === EDUCATION === */
.edu-timeline { max-width: 700px; margin: 0 auto; position: relative; padding-left: 40px; }
.edu-timeline::before {
    content: ''; position: absolute; left: 8px; top: 0; bottom: 0;
    width: 1px; background: linear-gradient(to bottom, var(--accent), var(--accent-2), transparent);
}
.edu-item { position: relative; margin-bottom: 48px; }
.edu-dot {
    position: absolute; left: -40px; top: 4px; width: 16px; height: 16px;
    border-radius: 50%; background: var(--bg); border: 2px solid var(--accent);
    z-index: 1;
}
.edu-item:hover .edu-dot { background: var(--accent); box-shadow: 0 0 20px rgba(41, 151, 255, 0.4); }
.edu-period { font-size: 0.8rem; color: var(--accent); font-weight: 600; letter-spacing: 1px; margin-bottom: 4px; }
.edu-content h3 { font-size: 1.3rem; font-weight: 700; margin-bottom: 4px; }
.edu-major { color: var(--text-secondary); font-size: 0.95rem; }
.edu-detail { color: var(--text-secondary); font-size: 0.85rem; margin-top: 4px; }

/* === EXPERIENCE CARDS === */
.exp-cards { display: grid; grid-template-columns: repeat(auto-fit, minmax(340px, 1fr)); gap: 24px; }
.exp-card {
    background: var(--card-bg); border: 1px solid var(--card-border);
    border-radius: var(--radius); padding: 36px; position: relative;
    transition: var(--transition); overflow: hidden;
}
.exp-card::before {
    content: ''; position: absolute; top: 0; left: 0; right: 0; height: 2px;
    background: var(--accent-gradient); opacity: 0; transition: opacity 0.4s;
}
.exp-card:hover { border-color: rgba(41, 151, 255, 0.2); transform: translateY(-6px); }
.exp-card:hover::before { opacity: 1; }
.exp-badge {
    display: inline-block; padding: 4px 12px; border-radius: 20px; font-size: 0.7rem;
    font-weight: 700; letter-spacing: 1px; text-transform: uppercase; margin-bottom: 16px;
    background: rgba(41, 151, 255, 0.12); color: var(--accent);
}
.exp-header h3 { font-size: 1.4rem; font-weight: 700; margin-bottom: 4px; }
.exp-role { color: var(--accent); font-size: 0.9rem; font-weight: 500; }
.exp-meta { font-size: 0.8rem; color: var(--text-secondary); margin: 12px 0; }
.exp-desc { color: var(--text-secondary); font-size: 0.95rem; line-height: 1.7; margin-bottom: 16px; }
.exp-tags { display: flex; flex-wrap: wrap; gap: 8px; margin-bottom: 16px; }
.exp-tags span {
    padding: 4px 12px; border-radius: 20px; font-size: 0.75rem; font-weight: 500;
    background: var(--tag-bg); color: var(--text-secondary);
    border: 1px solid var(--tag-border);
}
.exp-links { display: flex; flex-wrap: wrap; gap: 12px; }
.exp-link {
    color: var(--accent); font-size: 0.85rem; font-weight: 500;
    text-decoration: none; transition: 0.3s; display: inline-flex; align-items: center; gap: 4px;
}
.exp-link:hover { color: var(--text); text-decoration: underline; }

/* === AWARDS === */
.awards-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(240px, 1fr)); gap: 24px; }
.award-card {
    background: var(--card-bg); border: 1px solid var(--card-border);
    border-radius: var(--radius); padding: 36px; text-align: center;
    transition: var(--transition); text-decoration: none; color: inherit; display: block;
}
.award-card:hover { border-color: rgba(41, 151, 255, 0.3); transform: translateY(-6px); }
a.award-card:hover { border-color: rgba(41, 151, 255, 0.5); }
.award-icon { font-size: 2.5rem; margin-bottom: 16px; }
.award-card h3 { font-size: 1.1rem; font-weight: 700; margin-bottom: 8px; }
.award-card p { color: var(--text-secondary); font-size: 0.85rem; margin-bottom: 12px; }
.award-tag {
    display: inline-block; padding: 6px 16px; border-radius: 20px; font-size: 0.75rem;
    font-weight: 600; background: rgba(41, 151, 255, 0.12); color: var(--accent);
}
.award-source {
    display: block; margin-top: 12px; font-size: 0.78rem; color: var(--accent);
    opacity: 0.7; transition: 0.3s;
}
a.award-card:hover .award-source { opacity: 1; }

/* === PROJECTS === */
.projects-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(280px, 1fr)); gap: 24px; }
.project-card {
    background: var(--card-bg); border: 1px solid var(--card-border);
    border-radius: var(--radius); padding: 36px; text-decoration: none; color: inherit;
    transition: var(--transition); display: block; position: relative; overflow: hidden;
}
.project-card::after {
    content: ''; position: absolute; inset: 0; border-radius: var(--radius);
    background: linear-gradient(135deg, rgba(41, 151, 255, 0.05), rgba(191, 90, 242, 0.05));
    opacity: 0; transition: opacity 0.4s;
}
.project-card:hover { border-color: rgba(41, 151, 255, 0.3); transform: translateY(-6px); }
.project-card:hover::after { opacity: 1; }
.project-card > * { position: relative; z-index: 1; }
.project-stars { font-size: 0.85rem; font-weight: 600; color: var(--accent); margin-bottom: 12px; }
.project-card h3 { font-size: 1.2rem; font-weight: 700; margin-bottom: 10px; }
.project-card p { color: var(--text-secondary); font-size: 0.9rem; line-height: 1.6; margin-bottom: 16px; }
.project-tags { display: flex; flex-wrap: wrap; gap: 8px; }
.project-tags span {
    padding: 4px 12px; border-radius: 20px; font-size: 0.72rem; font-weight: 500;
    background: var(--tag-bg); color: var(--text-secondary);
}
.project-more { border-style: dashed; }
.project-more:hover { border-style: solid; }

/* === SKILLS === */
.skills-categories { display: grid; gap: 32px; max-width: 800px; margin: 0 auto; }
.skill-category {
    background: var(--card-bg); border: 1px solid var(--card-border);
    border-radius: var(--radius); padding: 32px;
}
.skill-category h3 {
    font-size: 0.8rem; letter-spacing: 3px; color: var(--accent);
    text-transform: uppercase; font-weight: 700; margin-bottom: 20px;
}
.skill-pills { display: flex; flex-wrap: wrap; gap: 10px; }
.skill-pills span {
    padding: 8px 20px; border-radius: 980px; font-size: 0.85rem; font-weight: 500;
    background: var(--pill-bg); border: 1px solid var(--pill-border);
    color: var(--text-secondary); transition: var(--transition);
}
.skill-pills span:hover {
    background: rgba(41, 151, 255, 0.1); border-color: rgba(41, 151, 255, 0.3);
    color: var(--text); transform: translateY(-2px);
}

/* === CONTACT === */
.contact-inner { text-align: center; max-width: 700px; margin: 0 auto; }
.contact-title {
    font-size: clamp(2.5rem, 5vw, 4rem); font-weight: 800;
    line-height: 1.15; letter-spacing: -1px; margin-bottom: 48px;
}
.contact-links { display: grid; grid-template-columns: repeat(3, 1fr); gap: 16px; margin-bottom: 32px; }
.contact-card {
    display: flex; align-items: center; gap: 16px; padding: 20px 24px;
    background: var(--card-bg); border: 1px solid var(--card-border);
    border-radius: 16px; text-decoration: none; color: var(--text);
    transition: var(--transition);
}
.contact-card:hover { border-color: rgba(41, 151, 255, 0.3); transform: translateY(-3px); }
.contact-icon { font-size: 1.4rem; }
.contact-text { font-size: 0.85rem; color: var(--text-secondary); }
.contact-card:hover .contact-text { color: var(--text); }
.contact-phone { color: var(--text-secondary); font-size: 0.9rem; margin-top: 16px; }

/* === FOOTER === */
.footer {
    padding: 40px 0; text-align: center;
    border-top: 1px solid var(--card-border);
}
.footer p { color: var(--text-secondary); font-size: 0.8rem; letter-spacing: 1px; }

/* === REVEAL ANIMATION === */
.reveal {
    opacity: 0; transform: translateY(40px);
    transition: opacity 0.8s cubic-bezier(0.16, 1, 0.3, 1), transform 0.8s cubic-bezier(0.16, 1, 0.3, 1);
}
.reveal.visible { opacity: 1; transform: translateY(0); }
.reveal:nth-child(2) { transition-delay: 0.1s; }
.reveal:nth-child(3) { transition-delay: 0.2s; }
.reveal:nth-child(4) { transition-delay: 0.3s; }

/* === THEME TOGGLE === */
.theme-toggle {
    background: none; border: none; cursor: pointer; font-size: 1.25rem;
    width: 40px; height: 40px; border-radius: 50%; display: flex;
    align-items: center; justify-content: center;
    color: var(--text); transition: var(--transition);
    background: var(--card-bg); border: 1px solid var(--card-border);
}
.theme-toggle:hover { transform: rotate(30deg) scale(1.1); border-color: var(--accent); }

body { transition: background 0.5s, color 0.5s; }

/* === RESPONSIVE === */
@media (max-width: 768px) {
    .nav-links { display: none; }
    .nav-toggle { display: block; }
    .hero { padding: 100px 20px 60px; }
    .hero-title { letter-spacing: -1px; }
    .about-grid { grid-template-columns: 1fr; gap: 40px; }
    .about-stats { grid-template-columns: 1fr 1fr; }
    .exp-cards { grid-template-columns: 1fr; }
    .awards-grid { grid-template-columns: 1fr 1fr; }
    .projects-grid { grid-template-columns: 1fr; }
    .contact-links { grid-template-columns: 1fr; }
    .edu-timeline { padding-left: 30px; }
}

@media (max-width: 480px) {
    .about-stats { grid-template-columns: 1fr; }
    .awards-grid { grid-template-columns: 1fr; }
    .hero-cta { flex-direction: column; align-items: center; }
}