/* =====================================================
   TRẦN TIẾN — PORTFOLIO  |  style.css
   ===================================================== */
*,*::before,*::after{box-sizing:border-box;margin:0;padding:0}
:root{
  --bg:#080c14;--bg-2:#0d1220;
  --surface:rgba(255,255,255,0.04);--surface-h:rgba(255,255,255,0.08);
  --border:rgba(255,255,255,0.08);--border-h:rgba(99,179,237,0.4);
  --accent:#60a5fa;--accent-2:#818cf8;--accent-glow:rgba(96,165,250,0.25);
  --text:#e2e8f0;--text-muted:#64748b;--text-dim:#94a3b8;
  --gradient:linear-gradient(135deg,#60a5fa 0%,#a78bfa 50%,#f472b6 100%);
  --section-py:100px;--container:1180px;
  --font:'Inter',sans-serif;--mono:'Fira Code',monospace;
  --radius:16px;--radius-sm:10px;--transition:0.3s cubic-bezier(0.4,0,0.2,1);
}
html{scroll-behavior:smooth}
body{font-family:var(--font);background:var(--bg);color:var(--text);line-height:1.6;overflow-x:hidden}
body.loading{overflow:hidden}
::-webkit-scrollbar{width:6px}::-webkit-scrollbar-track{background:var(--bg)}::-webkit-scrollbar-thumb{background:var(--accent);border-radius:3px}
::selection{background:rgba(96,165,250,0.3);color:#fff}
* { user-select: none; -webkit-user-select: none; -moz-user-select: none; -ms-user-select: none; }
.container{max-width:var(--container);margin:0 auto;padding:0 24px}
.gradient-text{background:var(--gradient);-webkit-background-clip:text;-webkit-text-fill-color:transparent;background-clip:text}
.accent{color:var(--accent)}
.glass-card{background:var(--surface);border:1px solid var(--border);border-radius:var(--radius);backdrop-filter:blur(12px);-webkit-backdrop-filter:blur(12px);transition:border-color var(--transition),transform var(--transition),box-shadow var(--transition)}
.glass-card:hover{border-color:var(--border-h);box-shadow:0 0 40px rgba(96,165,250,0.08)}
.btn{display:inline-flex;align-items:center;gap:8px;padding:14px 28px;border-radius:50px;font-family:var(--font);font-size:0.95rem;font-weight:600;cursor:pointer;border:none;text-decoration:none;transition:all var(--transition);position:relative;overflow:hidden;white-space:nowrap}
.btn::before{content:'';position:absolute;inset:0;background:rgba(255,255,255,0.1);opacity:0;transition:opacity var(--transition)}
.btn:hover::before{opacity:1}
.btn-primary{background:linear-gradient(135deg,#60a5fa,#818cf8);color:#fff;box-shadow:0 8px 32px rgba(96,165,250,0.35)}
.btn-primary:hover{transform:translateY(-2px);box-shadow:0 12px 40px rgba(96,165,250,0.5)}
.btn-ghost{background:transparent;color:var(--text-dim);border:1px solid var(--border)}
.btn-ghost:hover{color:var(--text);border-color:var(--accent);transform:translateY(-2px)}
.btn-outline{background:transparent;color:var(--accent);border:1px solid rgba(96,165,250,0.4)}
.btn-outline:hover{background:rgba(96,165,250,0.1);transform:translateY(-2px)}
.btn-sm{padding:10px 20px;font-size:0.88rem}

/* CURSOR */
.cursor,.cursor-follower{position:fixed;border-radius:50%;pointer-events:none;z-index:9999;transform:translate(-50%,-50%);transition:opacity 0.3s}
.cursor{width:10px;height:10px;background:var(--accent)}
.cursor-follower{width:36px;height:36px;border:1.5px solid rgba(96,165,250,0.5);transition:width 0.3s,height 0.3s,transform 0.1s}
.cursor-blink{display:inline-block;width:2px;height:1em;background:var(--accent);animation:blink 1s step-end infinite;vertical-align:text-bottom;margin-left:2px}
@keyframes blink{0%,100%{opacity:1}50%{opacity:0}}

/* LOADER */
.loader{position:fixed;inset:0;z-index:10000;background:var(--bg);display:flex;align-items:center;justify-content:center;transition:opacity 0.6s,visibility 0.6s}
.loader.hidden{opacity:0;visibility:hidden}
.loader-inner{text-align:center}
.loader-logo{display:block;font-size:3rem;font-weight:900;background:var(--gradient);-webkit-background-clip:text;-webkit-text-fill-color:transparent;background-clip:text;margin-bottom:32px;letter-spacing:-2px}
.loader-bar{width:200px;height:3px;background:var(--surface);border-radius:99px;overflow:hidden}
.loader-fill{height:100%;width:0%;background:var(--gradient);border-radius:99px;transition:width 0.1s linear}

/* HEADER */
.header{position:fixed;top:0;left:0;right:0;z-index:1000;padding:16px 0;transition:all var(--transition)}
.header.scrolled{background:rgba(8,12,20,0.9);backdrop-filter:blur(20px);-webkit-backdrop-filter:blur(20px);border-bottom:1px solid var(--border);padding:12px 0}
.nav{display:flex;align-items:center;gap:40px}
.nav-logo{font-size:1.4rem;font-weight:900;color:var(--text);text-decoration:none;letter-spacing:-0.5px;flex-shrink:0}
.nav-menu{display:flex;gap:4px;list-style:none;flex:1}
.nav-link{display:block;padding:8px 14px;color:var(--text-dim);text-decoration:none;font-size:0.92rem;font-weight:500;border-radius:8px;transition:all var(--transition);position:relative}
.nav-link:hover,.nav-link.active{color:var(--text);background:var(--surface-h)}
.nav-link.active::after{content:'';position:absolute;bottom:4px;left:50%;transform:translateX(-50%);width:4px;height:4px;border-radius:50%;background:var(--accent)}
.hamburger{display:none;flex-direction:column;gap:5px;background:none;border:none;cursor:pointer;padding:4px;margin-left:auto}
.hamburger span{display:block;width:24px;height:2px;background:var(--text);border-radius:99px;transition:all var(--transition)}
.hamburger.open span:nth-child(1){transform:translateY(7px) rotate(45deg)}
.hamburger.open span:nth-child(2){opacity:0}
.hamburger.open span:nth-child(3){transform:translateY(-7px) rotate(-45deg)}

/* SECTION */
.section{padding:var(--section-py) 0}
.section-header{text-align:center;margin-bottom:64px}
.section-tag{display:inline-flex;align-items:center;gap:8px;font-family:var(--mono);font-size:0.8rem;font-weight:500;color:var(--accent);letter-spacing:2px;text-transform:uppercase;margin-bottom:16px;padding:6px 14px;background:rgba(96,165,250,0.08);border:1px solid rgba(96,165,250,0.2);border-radius:99px}
.section-tag::before{content:'//';opacity:0.5}
.section-title{font-size:clamp(2rem,4vw,2.8rem);font-weight:800;line-height:1.15;letter-spacing:-1px}

/* HERO */
.hero{min-height:100vh;display:flex;align-items:center;position:relative;overflow:hidden;padding-top:80px}
.hero-bg{position:absolute;inset:0;z-index:0}
.orb{position:absolute;border-radius:50%;filter:blur(100px);opacity:0.15;animation:orbFloat 8s ease-in-out infinite}
.orb-1{width:600px;height:600px;background:#60a5fa;top:-200px;right:-100px;animation-delay:0s}
.orb-2{width:500px;height:500px;background:#818cf8;bottom:-100px;left:-150px;animation-delay:-3s}
.orb-3{width:400px;height:400px;background:#f472b6;top:50%;left:40%;animation-delay:-6s}
@keyframes orbFloat{0%,100%{transform:translate(0,0) scale(1)}33%{transform:translate(30px,-40px) scale(1.05)}66%{transform:translate(-20px,20px) scale(0.95)}}
.particles-canvas{position:absolute;inset:0;width:100%;height:100%;opacity:0.4}
.hero-content{position:relative;z-index:1;display:grid;grid-template-columns:1fr 1fr;gap:80px;align-items:center;padding-top:40px;padding-bottom:40px}
.hero-badge{display:inline-flex;align-items:center;gap:10px;padding:8px 16px;background:rgba(34,197,94,0.08);border:1px solid rgba(34,197,94,0.2);border-radius:99px;font-size:0.85rem;color:#4ade80;font-weight:500;margin-bottom:20px}
.badge-dot{width:8px;height:8px;border-radius:50%;background:#4ade80;animation:pulse-dot 2s ease-in-out infinite}
@keyframes pulse-dot{0%,100%{box-shadow:0 0 0 0 rgba(74,222,128,0.4)}50%{box-shadow:0 0 0 6px rgba(74,222,128,0)}}
.hero-greeting{font-size:1.1rem;color:var(--text-dim);font-weight:400;margin-bottom:8px}
.hero-name{font-size:clamp(3.5rem,7vw,5.5rem);font-weight:900;line-height:1;letter-spacing:-3px;margin-bottom:16px}
.hero-role-wrap{display:flex;align-items:center;font-size:1.3rem;color:var(--text-dim);margin-bottom:28px;min-height:2rem}
.hero-role{color:var(--accent);font-weight:600}
.hero-desc{font-size:1.05rem;color:var(--text-dim);line-height:1.75;max-width:520px;margin-bottom:36px}
.hero-desc strong{color:var(--text)}
.hero-actions{display:flex;gap:16px;flex-wrap:wrap;margin-bottom:48px}
.hero-stats{display:flex;align-items:center;gap:28px}
.stat-item{display:flex;flex-direction:column}
.stat-num{font-size:1.8rem;font-weight:800;color:var(--text);line-height:1;letter-spacing:-1px}
.stat-suffix{font-size:1.2rem;font-weight:700;color:var(--accent);display:inline}
.stat-label{font-size:0.78rem;color:var(--text-muted);font-weight:500;margin-top:4px;letter-spacing:0.5px}
.stat-divider{width:1px;height:36px;background:var(--border)}
.hero-visual{position:relative;display:flex;justify-content:center;align-items:center}
.hero-avatar-wrap{position:relative;width:320px;height:320px;display:flex;align-items:center;justify-content:center}
.avatar-ring{position:absolute;inset:-12px;border-radius:50%;border:2px solid transparent;background:linear-gradient(var(--bg),var(--bg)) padding-box,var(--gradient) border-box;animation:spin 8s linear infinite}
@keyframes spin{to{transform:rotate(360deg)}}
.avatar-glow{position:absolute;inset:0;border-radius:50%;background:var(--gradient);opacity:0.15;filter:blur(30px);animation:pulse 4s ease-in-out infinite}
@keyframes pulse{0%,100%{opacity:0.1}50%{opacity:0.25}}
.hero-avatar{width:280px;height:280px;border-radius:50%;object-fit:cover;object-position:top;position:relative;z-index:1;border:3px solid rgba(255,255,255,0.1)}
.avatar-badge-card{position:absolute;bottom:-10px;right:-20px;background:rgba(15,20,35,0.95);border:1px solid var(--border-h);border-radius:12px;padding:10px 16px;display:flex;align-items:center;gap:8px;font-size:0.85rem;font-weight:600;color:var(--accent);backdrop-filter:blur(10px);z-index:2;white-space:nowrap}
.tech-orbit{position:absolute;inset:-60px;border-radius:50%;pointer-events:none}
.tech-tag{position:absolute;top:50%;left:50%;transform-origin:0 0;transform:rotate(var(--a)) translateX(210px) rotate(calc(-1 * var(--a)));background:var(--surface);border:1px solid var(--border);border-radius:8px;padding:6px 12px;font-size:0.78rem;font-weight:600;font-family:var(--mono);color:var(--text-dim);white-space:nowrap;backdrop-filter:blur(8px);animation:orbitFloat 4s ease-in-out infinite}
.tech-tag:nth-child(1){animation-delay:0s}.tech-tag:nth-child(2){animation-delay:0.3s}.tech-tag:nth-child(3){animation-delay:0.6s}.tech-tag:nth-child(4){animation-delay:0.9s}.tech-tag:nth-child(5){animation-delay:1.2s}.tech-tag:nth-child(6){animation-delay:1.5s}
@keyframes orbitFloat{0%,100%{opacity:0.7}50%{opacity:1}}
.scroll-indicator{position:absolute;bottom:40px;left:50%;transform:translateX(-50%);display:flex;flex-direction:column;align-items:center;gap:8px;color:var(--text-muted);font-size:0.75rem;letter-spacing:2px;text-transform:uppercase;z-index:1}
.scroll-line{width:1px;height:50px;background:linear-gradient(to bottom,var(--accent),transparent);animation:scrollAnim 2s ease-in-out infinite}
@keyframes scrollAnim{0%,100%{transform:scaleY(1);opacity:1}50%{transform:scaleY(0.5);opacity:0.3}}

/* ABOUT */
.about{background:var(--bg-2)}
.about-grid{display:grid;grid-template-columns:1fr 1fr;gap:64px;align-items:start}
.about-text p{color:var(--text-dim);margin-bottom:20px;font-size:1.02rem;line-height:1.8}
.about-text strong{color:var(--text)}
.skills-grid{margin-top:32px;display:flex;flex-direction:column;gap:20px}
.skill-bar-header{display:flex;justify-content:space-between;margin-bottom:8px;font-size:0.9rem;font-weight:600}
.skill-bar-header span:last-child{color:var(--accent)}
.skill-bar-track{height:6px;background:var(--surface-h);border-radius:99px;overflow:hidden}
.skill-bar-fill{height:100%;width:0%;background:var(--gradient);border-radius:99px;transition:width 1.2s cubic-bezier(0.4,0,0.2,1)}
.about-cards{display:grid;grid-template-columns:1fr 1fr;gap:16px}
.about-card{padding:24px;border-radius:var(--radius)}
.about-card:hover{transform:translateY(-4px)}
.about-card-icon{font-size:1.8rem;margin-bottom:12px}
.about-card h3{font-size:0.95rem;font-weight:700;margin-bottom:8px;color:var(--text)}
.about-card p{font-size:0.85rem;color:var(--text-muted);line-height:1.6}

/* SERVICES */
.services-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:20px}
.service-card{padding:32px 24px;position:relative;overflow:hidden;cursor:default}
.service-card:hover{transform:translateY(-6px)}
.service-icon{font-size:2.4rem;margin-bottom:20px;display:block}
.service-card h3{font-size:1.05rem;font-weight:700;margin-bottom:12px;color:var(--text);line-height:1.3}
.service-card p{font-size:0.88rem;color:var(--text-muted);line-height:1.65;margin-bottom:20px}
.service-tags{display:flex;flex-wrap:wrap;gap:6px}
.service-tags span{padding:4px 10px;background:rgba(96,165,250,0.08);border:1px solid rgba(96,165,250,0.15);border-radius:6px;font-size:0.75rem;font-family:var(--mono);color:var(--accent)}

/* PROCESS */
.process{background:var(--bg-2)}
.process-timeline{display:grid;grid-template-columns:1fr 1fr;gap:24px;position:relative}
.process-timeline::before{content:'';position:absolute;top:50%;left:50%;transform:translate(-50%,-50%);width:1px;height:80%;background:linear-gradient(to bottom,transparent,var(--border),transparent)}
.process-step{display:flex;gap:20px;align-items:flex-start}
.process-step:nth-child(even){flex-direction:row-reverse}
.process-step-num{font-family:var(--mono);font-size:2.5rem;font-weight:700;background:var(--gradient);-webkit-background-clip:text;-webkit-text-fill-color:transparent;background-clip:text;flex-shrink:0;line-height:1;padding-top:8px}
.process-step-body{padding:24px;flex:1}
.process-step-body h3{font-size:1rem;font-weight:700;margin-bottom:8px;color:var(--text)}
.process-step-body p{font-size:0.88rem;color:var(--text-muted);line-height:1.6}

/* PROJECTS */
.projects-grid{display:grid;grid-template-columns:2fr 1fr;gap:24px}
.project-card{padding:36px;position:relative;overflow:hidden}
.project-card:hover{transform:translateY(-4px)}
.project-card-header{display:flex;align-items:center;justify-content:space-between;margin-bottom:20px}
.project-featured-badge{font-size:0.8rem;font-weight:600;color:#fbbf24;background:rgba(251,191,36,0.08);border:1px solid rgba(251,191,36,0.2);padding:4px 12px;border-radius:99px}
.project-category{font-family:var(--mono);font-size:0.75rem;color:var(--accent);text-transform:uppercase;letter-spacing:1px}
.project-title{font-size:1.6rem;font-weight:800;color:var(--text);margin-bottom:12px;letter-spacing:-0.5px}
.project-desc{color:var(--text-dim);margin-bottom:12px;line-height:1.7}
.project-details{color:var(--text-muted);font-size:0.88rem;line-height:1.7;margin-bottom:24px;padding:16px;background:rgba(255,255,255,0.02);border-left:2px solid var(--accent);border-radius:0 8px 8px 0}
.project-tech{display:flex;flex-wrap:wrap;gap:8px;margin-bottom:28px}
.project-tech span{padding:5px 12px;background:var(--surface);border:1px solid var(--border);border-radius:8px;font-family:var(--mono);font-size:0.8rem;color:var(--text-dim)}
.project-glow{position:absolute;top:-60px;right:-60px;width:200px;height:200px;background:radial-gradient(circle,rgba(96,165,250,0.15),transparent 70%);pointer-events:none}
.project-card.coming{display:flex;flex-direction:column;align-items:center;justify-content:center;text-align:center;gap:16px;border-style:dashed}
.coming-icon{font-size:3rem}
.project-card.coming h3{font-size:1.1rem;font-weight:700}
.project-card.coming p{color:var(--text-muted);font-size:0.9rem}
.coming-badge{padding:6px 14px;background:rgba(251,191,36,0.08);border:1px solid rgba(251,191,36,0.2);border-radius:99px;font-size:0.8rem;color:#fbbf24;font-weight:500}

/* CONTACT */
.contact{background:var(--bg-2)}
.contact-inner{padding:72px;display:grid;grid-template-columns:1fr 1fr;gap:72px;align-items:center;position:relative;overflow:hidden}
.contact-inner::before{content:'';position:absolute;top:-80px;right:-80px;width:320px;height:320px;background:radial-gradient(circle,rgba(96,165,250,0.08),transparent 70%);pointer-events:none}
.contact-cta .section-tag{margin-bottom:20px}
.contact-cta .section-title{margin-bottom:16px}
.contact-cta p{color:var(--text-muted);line-height:1.7;margin-bottom:32px}
.contact-actions{display:flex;gap:12px;flex-wrap:wrap}
.contact-links{display:flex;flex-direction:column;gap:16px}
.contact-link{display:flex;align-items:center;gap:16px;padding:16px 20px;background:var(--surface);border:1px solid var(--border);border-radius:var(--radius-sm);text-decoration:none;transition:all var(--transition)}
.contact-link:hover{border-color:var(--border-h);background:var(--surface-h);transform:translateX(6px)}
.contact-link-icon{width:44px;height:44px;border-radius:10px;background:rgba(96,165,250,0.08);display:flex;align-items:center;justify-content:center;flex-shrink:0}
.contact-link-icon svg{width:22px;height:22px;color:var(--accent)}
.zalo-icon{background:rgba(0,120,255,0.1)}
.email-icon{background:rgba(251,146,60,0.1)}
.email-icon svg{color:#fb923c}
.contact-link-info{display:flex;flex-direction:column}
.contact-link-label{font-size:0.75rem;color:var(--text-muted);font-weight:500;letter-spacing:0.5px}
.contact-link-value{font-size:0.95rem;color:var(--text);font-weight:600}

/* FOOTER */
.footer{padding:40px 0;border-top:1px solid var(--border)}
.footer-inner{display:flex;flex-direction:column;align-items:center;gap:8px;text-align:center}
.footer-logo{font-size:1.3rem;font-weight:900;color:var(--text);text-decoration:none;margin-bottom:4px}
.footer-copy,.footer-note{font-size:0.85rem;color:var(--text-muted)}

/* BACK TO TOP */
.back-to-top{position:fixed;bottom:32px;right:32px;width:44px;height:44px;background:var(--accent);border:none;border-radius:50%;cursor:pointer;display:flex;align-items:center;justify-content:center;color:#fff;box-shadow:0 8px 24px rgba(96,165,250,0.4);opacity:0;transform:translateY(20px);transition:all var(--transition);z-index:100}
.back-to-top.visible{opacity:1;transform:translateY(0)}
.back-to-top:hover{transform:translateY(-4px) scale(1.05)}

/* AOS */
[data-aos]{opacity:0;transform:translateY(32px);transition:opacity 0.7s ease,transform 0.7s ease}
[data-aos="fade-right"]{transform:translateX(-32px)}
[data-aos="fade-left"]{transform:translateX(32px)}
[data-aos].aos-animate{opacity:1;transform:none}

/* RESPONSIVE */
@media(max-width:1024px){
  .services-grid{grid-template-columns:repeat(2,1fr)}
  .hero-content{gap:48px}
  .contact-inner{padding:48px;gap:48px}
}
@media(max-width:768px){
  :root{--section-py:72px}
  .nav-menu{display:none;position:fixed;top:72px;left:0;right:0;background:rgba(8,12,20,0.98);backdrop-filter:blur(20px);flex-direction:column;padding:24px;gap:4px;border-bottom:1px solid var(--border)}
  .nav-menu.open{display:flex}
  .hamburger{display:flex}
  .nav a.btn-outline{display:none}
  .hero-content{grid-template-columns:1fr;text-align:center;gap:48px}
  .hero-text{order:2}.hero-visual{order:1}
  .hero-desc{margin:0 auto 36px}
  .hero-actions,.hero-stats{justify-content:center}
  .tech-orbit{display:none}
  .hero-avatar-wrap{width:220px;height:220px}
  .hero-avatar{width:190px;height:190px}
  .hero-name{font-size:3rem}
  .about-grid{grid-template-columns:1fr;gap:40px}
  .about-cards{grid-template-columns:1fr 1fr}
  .services-grid{grid-template-columns:1fr}
  .process-timeline{grid-template-columns:1fr}
  .process-timeline::before{display:none}
  .process-step:nth-child(even){flex-direction:row}
  .projects-grid{grid-template-columns:1fr}
  .contact-inner{grid-template-columns:1fr;padding:36px 28px;gap:36px}
  .scroll-indicator,.cursor,.cursor-follower{display:none}
}
@media(max-width:480px){
  .about-cards{grid-template-columns:1fr}
  .hero-stats{gap:16px}
  .stat-num{font-size:1.4rem}
}