/* =========================================================
   RSK.dev — Redwan Sharafat Kabir
   Light theme: monochrome (black / white / grey)
   Dark theme: original teal + emerald palette
   ========================================================= */

:root{
  /* Brand palette — monochrome (LIGHT / default) */
  --primary:#1a1a1a;
  --primary-light:#3a3a3a;
  --primary-dark:#000000;
  --accent:#1f1f1f;
  --accent-hover:#000000;

  /* Surfaces / depth — LIGHT (default) */
  --bg:#ffffff;
  --bg2:#f4f4f4;
  --bg3:#e9e9e9;
  --surface:#ffffff;
  --surface2:#f6f6f6;
  --surface-glass:rgba(255,255,255,0.78);
  --border:rgba(0,0,0,0.12);
  --border-strong:rgba(0,0,0,0.32);

  /* Text */
  --text:#111111;
  --text2:#454545;
  --text3:#787878;
  --white:#ffffff;
  --ink:#ffffff;               /* text on accent buttons */

  /* Signature gradient — pure greyscale */
  --grad-accent:linear-gradient(120deg,#000000 0%,#3d3d3d 45%,#8a8a8a 100%);
  --grad-line:linear-gradient(90deg,transparent,#1a1a1a,transparent);

  /* Effects */
  --shadow:0 24px 70px -20px rgba(0,0,0,0.18);
  --shadow-sm:0 10px 30px -12px rgba(0,0,0,0.14);
  --glow:0 0 0 1px rgba(0,0,0,0.22),0 18px 50px -16px rgba(0,0,0,0.20);

  /* Accent-tinted tokens used for badges / rings / chips / glows */
  --tint:rgba(0,0,0,0.06);
  --tint-strong:rgba(0,0,0,0.10);
  --tag-bg:rgba(0,0,0,0.055);
  --selection-bg:rgba(0,0,0,0.15);
  --citation-bg:rgba(0,0,0,0.045);
  --accent-glow:rgba(0,0,0,0.35);
  --btn-shadow:rgba(0,0,0,0.35);
  --btn-shadow-hover:rgba(0,0,0,0.45);
  --hero-glow1:rgba(0,0,0,0.06);
  --hero-glow2:rgba(0,0,0,0.04);

  /* System */
  --nav-h:70px;
  --radius:18px;
  --radius-sm:12px;
  --maxw:1200px;

  --font-display:'Space Grotesk',ui-sans-serif,system-ui,sans-serif;
  --font-body:'DM Sans',ui-sans-serif,system-ui,sans-serif;
  --font-mono:'JetBrains Mono',ui-monospace,monospace;
}

[data-theme="dark"]{
  /* Brand palette — original teal + emerald */
  --primary:#004052;
  --primary-light:#005a73;
  --primary-dark:#002a37;
  --accent:#4ade80;
  --accent-hover:#22c55e;

  /* Surfaces / depth */
  --bg:#0a0f14;
  --bg2:#0f1921;
  --bg3:#162331;
  --surface:#12202c;
  --surface2:#17293a;
  --surface-glass:rgba(18,32,44,0.72);
  --border:rgba(90,138,154,0.18);
  --border-strong:rgba(74,222,128,0.30);

  /* Text */
  --text:#e8f4f8;
  --text2:#a3c4d0;
  --text3:#6d94a3;
  --ink:#04140d;

  /* Signature gradient */
  --grad-accent:linear-gradient(120deg,#4ade80 0%,#2dd4a7 45%,#005a73 100%);
  --grad-line:linear-gradient(90deg,transparent,var(--accent),transparent);

  /* Effects */
  --shadow:0 24px 70px -20px rgba(0,0,0,0.65);
  --shadow-sm:0 10px 30px -12px rgba(0,0,0,0.55);
  --glow:0 0 0 1px rgba(74,222,128,0.25),0 18px 50px -16px rgba(74,222,128,0.22);

  /* Accent-tinted tokens */
  --tint:rgba(74,222,128,.10);
  --tint-strong:rgba(74,222,128,.12);
  --tag-bg:rgba(0,64,82,.28);
  --selection-bg:rgba(74,222,128,0.28);
  --citation-bg:rgba(0,64,82,.22);
  --accent-glow:rgba(74,222,128,.6);
  --btn-shadow:rgba(74,222,128,.5);
  --btn-shadow-hover:rgba(74,222,128,.65);
  --hero-glow1:rgba(0,90,115,0.35);
  --hero-glow2:rgba(74,222,128,0.08);
}

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

html{
  scroll-behavior:smooth;
  scroll-padding-top:calc(var(--nav-h) + 14px);
  font-size:16px;
  -webkit-text-size-adjust:100%;
}

body{
  font-family:var(--font-body);
  background:var(--bg);
  color:var(--text);
  line-height:1.65;
  overflow-x:hidden;
  transition:background .35s ease,color .35s ease;
  position:relative;
}

/* Ambient page grain for premium depth */
body::before{
  content:"";position:fixed;inset:0;z-index:0;pointer-events:none;
  opacity:.03;mix-blend-mode:overlay;
  background-image:url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='140' height='140'%3E%3Cfilter id='n'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.85' numOctaves='2' stitchTiles='stitch'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23n)'/%3E%3C/svg%3E");
}

/* Keep all real content above the grain */
nav,main,section,footer,.social-float,.mobile-menu,.scroll-progress{position:relative;z-index:1}

::selection{background:var(--selection-bg);color:var(--text)}

::-webkit-scrollbar{width:10px}
::-webkit-scrollbar-track{background:var(--bg2)}
::-webkit-scrollbar-thumb{background:linear-gradient(var(--primary-light),var(--primary));border-radius:20px;border:3px solid var(--bg2)}
::-webkit-scrollbar-thumb:hover{background:var(--accent-hover)}

a{color:inherit}
img{max-width:100%;display:block}

:focus-visible{outline:2px solid var(--accent-hover);outline-offset:3px;border-radius:6px}

/* ===================== NAV ===================== */
.scroll-progress{
  position:fixed;top:0;left:0;height:2px;width:0;z-index:1200;
  background:var(--grad-accent);box-shadow:0 0 12px var(--accent-glow);
  transition:width .1s linear;
}

nav{
  position:fixed;top:0;left:0;right:0;z-index:1000;
  padding:0 clamp(1.1rem,5vw,3rem);
  display:flex;align-items:center;justify-content:space-between;
  height:var(--nav-h);
  background:var(--surface-glass);
  backdrop-filter:blur(22px) saturate(140%);
  -webkit-backdrop-filter:blur(22px) saturate(140%);
  border-bottom:1px solid var(--border);
  transition:background .35s ease,border-color .35s ease,box-shadow .35s ease;
}
nav.scrolled{box-shadow:0 10px 40px -18px rgba(0,0,0,.5)}

.nav-logo{
  font-family:var(--font-display);font-weight:700;font-size:1.28rem;
  color:var(--text);letter-spacing:-.5px;text-decoration:none;
  display:inline-flex;align-items:center;gap:.15rem;
}
.nav-logo span{
  background:var(--grad-accent);-webkit-background-clip:text;background-clip:text;
  -webkit-text-fill-color:transparent;font-weight:700;
}

.nav-links{display:flex;gap:2.1rem;list-style:none}
.nav-links a{
  font-family:var(--font-mono);
  font-size:.76rem;font-weight:400;text-decoration:none;
  color:var(--text2);letter-spacing:.6px;text-transform:uppercase;
  transition:color .2s ease;padding:6px 0;position:relative;
}
.nav-links a::after{
  content:"";position:absolute;bottom:0;left:0;width:0;height:2px;border-radius:2px;
  background:var(--grad-accent);transition:width .3s cubic-bezier(.4,0,.2,1);
}
.nav-links a:hover{color:var(--text)}
.nav-links a:hover::after,
.nav-links a.active::after{width:100%}
.nav-links a.active{color:var(--accent-hover)}

.nav-right{display:flex;align-items:center;gap:.9rem}
.theme-toggle{
  background:var(--surface);border:1px solid var(--border);
  border-radius:50px;padding:7px 15px;cursor:pointer;
  display:flex;align-items:center;gap:8px;
  font-size:.74rem;font-weight:500;color:var(--text2);
  transition:all .2s ease;font-family:var(--font-mono);
}
.theme-toggle:hover{border-color:var(--border-strong);color:var(--accent-hover);transform:translateY(-1px)}
.theme-toggle .icon{font-size:.95rem;line-height:1}

.hamburger{
  display:none;flex-direction:column;gap:5px;
  cursor:pointer;padding:8px;border:none;background:none;
}
.hamburger span{display:block;width:24px;height:2px;background:var(--text);border-radius:2px;transition:all .3s ease}

.mobile-menu{
  display:none;position:fixed;top:var(--nav-h);left:0;right:0;z-index:999;
  background:var(--surface-glass);backdrop-filter:blur(22px);-webkit-backdrop-filter:blur(22px);
  border-bottom:1px solid var(--border);
  padding:1.3rem clamp(1.1rem,5vw,3rem) 1.8rem;flex-direction:column;gap:.4rem;
  animation:menuDrop .25s ease;
}
@keyframes menuDrop{from{opacity:0;transform:translateY(-8px)}to{opacity:1;transform:none}}
.mobile-menu.open{display:flex}
.mobile-menu a{
  font-family:var(--font-mono);
  font-size:.9rem;font-weight:400;color:var(--text2);text-decoration:none;
  text-transform:uppercase;letter-spacing:.6px;padding:.75rem 0;
  border-bottom:1px solid var(--border);transition:color .2s ease,padding-left .2s ease;
}
.mobile-menu a:hover{color:var(--accent-hover);padding-left:.4rem}
.theme-toggle-mobile{display:none}

/* ===================== SOCIAL FLOAT ===================== */
.social-float{
  position:fixed;right:22px;top:50%;transform:translateY(-50%);
  z-index:500;display:flex;flex-direction:column;gap:12px;
}
.social-float::after{
  content:"";width:1px;height:70px;margin:6px auto 0;
  background:linear-gradient(var(--border-strong),transparent);
}
.sf-link{
  width:42px;height:42px;border-radius:12px;
  background:var(--surface-glass);border:1px solid var(--border);
  backdrop-filter:blur(10px);-webkit-backdrop-filter:blur(10px);
  display:flex;align-items:center;justify-content:center;
  text-decoration:none;transition:all .25s cubic-bezier(.4,0,.2,1);position:relative;
}
.sf-link:hover{border-color:transparent;background:var(--grad-accent);transform:translateY(-3px) scale(1.05);box-shadow:var(--glow)}
.sf-link svg{width:18px;height:18px;fill:var(--text2);transition:fill .2s ease}
.sf-link:hover svg{fill:var(--ink)}
.sf-tooltip{
  position:absolute;right:54px;background:var(--surface2);
  border:1px solid var(--border);border-radius:8px;
  padding:5px 11px;font-size:.72rem;color:var(--text);
  white-space:nowrap;opacity:0;pointer-events:none;transition:opacity .2s ease,transform .2s ease;
  font-family:var(--font-mono);transform:translateX(6px);
}
.sf-link:hover .sf-tooltip{opacity:1;transform:translateX(0)}

/* ===================== BUTTONS ===================== */
.btn-primary,.btn-outline,.submit-btn{
  font-family:var(--font-body);font-weight:600;font-size:.9rem;letter-spacing:.3px;
  border-radius:10px;padding:13px 28px;text-decoration:none;cursor:pointer;
  display:inline-flex;align-items:center;justify-content:center;gap:.5rem;
  transition:all .25s cubic-bezier(.4,0,.2,1);position:relative;overflow:hidden;
}
.btn-primary,.submit-btn{
  background:var(--grad-accent);color:var(--ink);border:none;font-weight:700;
  box-shadow:0 10px 30px -12px var(--btn-shadow);
}
.btn-primary::after,.submit-btn::after{
  content:"";position:absolute;inset:0;
  background:linear-gradient(120deg,rgba(255,255,255,.35),transparent 45%);
  opacity:0;transition:opacity .25s ease;
}
.btn-primary:hover,.submit-btn:hover{transform:translateY(-3px);box-shadow:0 18px 44px -14px var(--btn-shadow-hover)}
.btn-primary:hover::after,.submit-btn:hover::after{opacity:1}

.btn-outline{
  background:transparent;color:var(--text);
  border:1px solid var(--border-strong);
}
.btn-outline:hover{color:var(--accent-hover);border-color:var(--accent-hover);transform:translateY(-3px);background:var(--tint)}

/* ===================== HERO ===================== */
#home{
  min-height:100vh;min-height:100svh;
  display:flex;align-items:center;
  max-width:100%;
  padding:calc(var(--nav-h) + 3.2rem) 0 3.2rem;
  position:relative;overflow:hidden;
}
@supports (align-items:safe center){#home{align-items:safe center}}

.hero-bg{
  position:absolute;inset:0;z-index:0;
  background:
    radial-gradient(ellipse 60% 55% at 82% 42%,var(--hero-glow1) 0%,transparent 62%),
    radial-gradient(ellipse 46% 60% at 8% 88%,var(--hero-glow2) 0%,transparent 55%);
}
.hero-grid{
  position:absolute;inset:0;z-index:0;
  background-image:linear-gradient(var(--border) 1px,transparent 1px),linear-gradient(90deg,var(--border) 1px,transparent 1px);
  background-size:64px 64px;
  mask-image:radial-gradient(ellipse 85% 80% at 50% 45%,#000 0%,transparent 100%);
  -webkit-mask-image:radial-gradient(ellipse 85% 80% at 50% 45%,#000 0%,transparent 100%);
  opacity:.35;
}
.hero-neural{position:absolute;inset:0;z-index:0;pointer-events:none;opacity:.5}

.hero-inner{
  position:relative;z-index:2;
  width:90%;max-width:var(--maxw);margin:0 auto;
  display:grid;grid-template-columns:1fr 400px;gap:clamp(2rem,5vw,4.5rem);align-items:center;
}

.hero-badge{
  display:inline-flex;align-items:center;gap:9px;
  background:var(--tint);border:1px solid var(--border-strong);
  border-radius:50px;padding:7px 17px;
  font-size:.75rem;font-family:var(--font-mono);color:var(--accent-hover);
  margin-bottom:1.6rem;letter-spacing:.4px;backdrop-filter:blur(6px);
}

h1.hero-title{
  font-family:var(--font-display);font-size:clamp(2.6rem,6vw,4.4rem);
  font-weight:700;line-height:1.04;letter-spacing:-2px;margin-bottom:1.3rem;
}
h1.hero-title .name{
  background:var(--grad-accent);-webkit-background-clip:text;background-clip:text;
  -webkit-text-fill-color:transparent;
}
.hero-sub{
  font-size:clamp(1rem,1.3vw,1.14rem);color:var(--text2);max-width:500px;
  margin-bottom:2.2rem;line-height:1.75;
}
.hero-sub strong{color:var(--text);font-weight:600}
.hero-cta{display:flex;gap:1rem;flex-wrap:wrap;margin-bottom:3rem}

.hero-stats{display:flex;gap:2.6rem}
.stat{display:flex;flex-direction:column;position:relative;padding-left:1rem}
.stat::before{content:"";position:absolute;left:0;top:4px;bottom:4px;width:2px;border-radius:2px;background:var(--grad-accent)}
.stat-num{font-family:var(--font-display);font-size:2rem;font-weight:700;color:var(--text);line-height:1}
.stat-label{font-size:.74rem;color:var(--text3);letter-spacing:.6px;text-transform:uppercase;font-family:var(--font-mono);margin-top:.4rem}

/* Credential card */
.hero-card{
  background:linear-gradient(160deg,var(--surface),var(--surface2));
  border:1px solid var(--border);
  border-radius:var(--radius);padding:1.9rem;
  box-shadow:var(--shadow);position:relative;overflow:hidden;
}
.hero-card::before{content:"";position:absolute;top:0;left:0;right:0;height:1px;background:var(--grad-line)}
.hero-card::after{content:"";position:absolute;top:-40%;right:-30%;width:70%;height:70%;background:radial-gradient(circle,var(--tint),transparent 70%);pointer-events:none}

.hc-avatar-wrap{position:relative;width:210px;height:210px;margin:0 auto 1.4rem;border-radius:14px;padding:3px;background:var(--grad-accent)}
.hc-avatar-photo,.hc-avatar-fallback{width:100%;height:100%;border-radius:11px;object-fit:cover;background:var(--bg2);display:block}
.hc-avatar-fallback{display:none;align-items:center;justify-content:center;font-family:var(--font-display);font-weight:700;font-size:3rem;letter-spacing:1px;color:var(--accent-hover)}

.hc-name{font-family:var(--font-display);font-size:1.2rem;font-weight:700;text-align:center;margin-bottom:.3rem}
.hc-role{font-size:.8rem;color:var(--accent-hover);font-family:var(--font-mono);text-align:center;margin-bottom:1.5rem}
.hc-info{display:flex;flex-direction:column;gap:.15rem;border-top:1px solid var(--border);padding-top:1.2rem}
.hc-info-row{display:flex;align-items:center;gap:12px;font-size:.83rem;color:var(--text2);padding:.5rem 0;border-radius:8px;transition:color .2s ease}
.hc-info-row:hover{color:var(--text)}
.hc-info-row .ico{width:30px;height:30px;flex-shrink:0;border-radius:8px;background:var(--tint);border:1px solid var(--border);display:flex;align-items:center;justify-content:center;color:var(--accent-hover);font-size:.82rem}

/* ===================== SECTION PRIMITIVES ===================== */
section{padding:clamp(70px,9vw,110px) clamp(1.1rem,5vw,3rem);max-width:var(--maxw);margin:0 auto}
.section-head{margin-bottom:clamp(2.2rem,4vw,3.4rem)}
.section-label{
  display:inline-flex;align-items:center;gap:.6rem;font-family:var(--font-mono);
  font-size:.74rem;color:var(--accent-hover);letter-spacing:2px;
  text-transform:uppercase;margin-bottom:.9rem;
}
.section-label::before{content:"";width:26px;height:1px;background:var(--grad-accent)}
.section-title{
  font-family:var(--font-display);font-size:clamp(1.9rem,3.4vw,2.7rem);
  font-weight:700;letter-spacing:-1.2px;margin-bottom:1rem;color:var(--text);line-height:1.1;
}
.section-title span{
  background:var(--grad-accent);-webkit-background-clip:text;background-clip:text;-webkit-text-fill-color:transparent;
}
.section-desc{color:var(--text2);max-width:540px;font-size:1rem;line-height:1.7;margin-bottom:3rem}
.divider{width:64px;height:3px;background:var(--grad-accent);border-radius:2px}

/* Shared card hover accent */
.card-accent{position:relative;overflow:hidden}
.card-accent::before{content:"";position:absolute;top:0;left:0;right:0;height:2px;background:var(--grad-line);opacity:0;transition:opacity .3s ease}
.card-accent:hover::before{opacity:1}

/* ===================== ABOUT ===================== */
#about{max-width:var(--maxw)}
.about-grid{display:grid;grid-template-columns:1.05fr 1fr;gap:clamp(2rem,5vw,4rem);align-items:start}
.about-text p{color:var(--text2);line-height:1.85;margin-bottom:1.1rem;font-size:.99rem}
.about-text p strong{color:var(--text);font-weight:600}
.about-highlights{display:grid;grid-template-columns:1fr 1fr;gap:1rem;margin-top:1.8rem}
.highlight-card{
  background:linear-gradient(160deg,var(--surface),var(--surface2));
  border:1px solid var(--border);border-radius:var(--radius-sm);padding:1.3rem;
  transition:border-color .25s ease,transform .25s ease,box-shadow .25s ease;
}
.highlight-card:hover{border-color:var(--border-strong);transform:translateY(-4px);box-shadow:var(--shadow-sm)}
.hc-icon{
  width:42px;height:42px;border-radius:11px;margin-bottom:.9rem;
  background:var(--tint);border:1px solid var(--border-strong);
  display:flex;align-items:center;justify-content:center;color:var(--accent-hover);font-size:1.1rem;
}
.hc-hl-title{font-family:var(--font-display);font-weight:600;font-size:.95rem;margin-bottom:.3rem;color:var(--text)}
.hc-hl-text{font-size:.8rem;color:var(--text3);line-height:1.55}

.sub-label{font-family:var(--font-mono);font-size:.74rem;color:var(--accent-hover);letter-spacing:1.5px;text-transform:uppercase;margin-bottom:1.4rem}

/* Timeline */
.timeline{position:relative;padding-left:2.1rem}
.timeline::before{content:"";position:absolute;left:7px;top:6px;bottom:6px;width:2px;background:linear-gradient(to bottom,var(--accent-hover),var(--primary-light) 60%,transparent)}
.tl-item{position:relative;margin-bottom:2rem}
.tl-item:last-child{margin-bottom:0}
.tl-dot{position:absolute;left:-2.1rem;top:5px;width:14px;height:14px;border-radius:50%;background:var(--accent-hover);box-shadow:0 0 0 4px var(--bg),0 0 14px var(--accent-glow)}
.tl-period{font-family:var(--font-mono);font-size:.73rem;color:var(--accent-hover);letter-spacing:.5px;margin-bottom:.35rem}
.tl-title{font-family:var(--font-display);font-weight:600;font-size:1.02rem;margin-bottom:.15rem;color:var(--text)}
.tl-place{font-size:.83rem;color:var(--text3);margin-bottom:.5rem;font-style:italic}
.tl-tags{display:flex;flex-wrap:wrap;gap:6px;margin-top:.6rem}
.tl-tag,.ptech,.tag{
  background:var(--tag-bg);border:1px solid var(--border);
  border-radius:6px;padding:3px 9px;font-size:.7rem;
  color:var(--text3);font-family:var(--font-mono);
}

/* ===================== FULL-BLEED SECTION WRAPPER ===================== */
.band{background:var(--bg2);position:relative;max-width:100%;padding:0;margin:0}
.band::before,.band::after{content:"";position:absolute;left:0;right:0;height:1px;background:var(--border)}
.band::before{top:0}.band::after{bottom:0}
.band .inner{max-width:var(--maxw);margin:0 auto;padding:clamp(70px,9vw,110px) clamp(1.1rem,5vw,3rem)}

/* ===================== SKILLS ===================== */
.skills-grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(140px,1fr));gap:1rem}
.skill-card{
  background:linear-gradient(160deg,var(--surface),var(--surface2));
  border:1px solid var(--border);border-radius:var(--radius-sm);
  padding:1.4rem 1rem;text-align:center;transition:all .25s cubic-bezier(.4,0,.2,1);cursor:default;
}
.skill-card:hover{border-color:var(--border-strong);transform:translateY(-5px);box-shadow:var(--shadow-sm)}
.skill-icon{font-size:2.1rem;margin-bottom:.6rem;color:var(--text2);transition:transform .25s ease}
.skill-card:hover .skill-icon{transform:scale(1.12)}

.skill-name{font-size:.82rem;font-weight:600;color:var(--text);font-family:var(--font-mono)}
.skill-cat{font-size:.7rem;color:var(--text3);margin-top:.25rem}

/* ===================== EXPERIENCE ===================== */
#experience{max-width:var(--maxw)}
.exp-card{
  background:linear-gradient(160deg,var(--surface),var(--surface2));
  border:1px solid var(--border);border-radius:var(--radius);
  padding:2rem clamp(1.4rem,3vw,2.2rem);margin-bottom:1.5rem;
  position:relative;overflow:hidden;transition:border-color .25s ease,box-shadow .25s ease,transform .25s ease;
}
.exp-card:last-child{margin-bottom:0}
.exp-card:hover{border-color:var(--border-strong);box-shadow:var(--shadow-sm);transform:translateY(-3px)}
.exp-card::before{content:"";position:absolute;left:0;top:0;bottom:0;width:3px;background:var(--grad-accent)}
.exp-header{display:flex;justify-content:space-between;align-items:center;margin-bottom:.4rem;flex-wrap:wrap;gap:.6rem}
.exp-title{font-family:var(--font-display);font-weight:600;font-size:1.15rem}
.exp-period{font-family:var(--font-mono);font-size:.75rem;background:var(--tint);color:var(--accent-hover);border:1px solid var(--border-strong);border-radius:50px;padding:4px 12px;white-space:nowrap}
.exp-company{font-size:.88rem;color:var(--accent-hover);margin-bottom:1.2rem;font-family:var(--font-mono)}
.exp-list{list-style:none;display:flex;flex-direction:column;gap:.7rem}
.exp-list li{font-size:.9rem;color:var(--text2);padding-left:1.5rem;position:relative;line-height:1.65}
.exp-list li::before{content:"";position:absolute;left:0;top:.55em;width:7px;height:7px;border-radius:2px;background:var(--grad-accent)}

/* ===================== PROJECTS ===================== */
.services-grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(300px,1fr));gap:1.5rem}
.project-card{
  background:linear-gradient(160deg,var(--surface),var(--surface2));
  border:1px solid var(--border);border-radius:var(--radius);overflow:hidden;
  transition:all .3s cubic-bezier(.4,0,.2,1);
}
.project-card:hover{border-color:var(--border-strong);transform:translateY(-6px);box-shadow:var(--shadow)}
.project-img{
  height:170px;display:flex;align-items:center;justify-content:center;
  font-size:3rem;position:relative;color:var(--accent-hover);
  background:radial-gradient(circle at 30% 25%,var(--tint),transparent 55%),linear-gradient(135deg,var(--surface2),var(--bg3));
  border-bottom:1px solid var(--border);
}
.project-img::after{content:"";position:absolute;inset:0;background:linear-gradient(to bottom,transparent 55%,rgba(10,15,20,.25))}
.project-badge{
  position:absolute;top:14px;right:14px;z-index:1;
  background:var(--bg);border:1px solid var(--border-strong);
  border-radius:50px;padding:4px 12px;
  font-size:.68rem;font-family:var(--font-mono);color:var(--accent-hover);
}
.project-body{padding:1.6rem}
.project-title{font-family:var(--font-display);font-weight:600;font-size:1.1rem;margin-bottom:.55rem}
.project-desc{font-size:.86rem;color:var(--text2);line-height:1.65;margin-bottom:1.1rem}
.project-tech{display:flex;flex-wrap:wrap;gap:6px}

/* ===================== PUBLICATIONS ===================== */
.pub-grid{display:flex;flex-direction:column;gap:1.5rem}
.pub-card{
  background:linear-gradient(160deg,var(--surface),var(--surface2));
  border:1px solid var(--border);border-radius:var(--radius);overflow:hidden;
  transition:border-color .3s ease,box-shadow .3s ease,transform .3s ease;
  display:grid;grid-template-columns:210px 1fr;
}
.pub-card:hover{border-color:var(--border-strong);box-shadow:var(--shadow);transform:translateY(-3px)}
.pub-img{
  display:flex;align-items:center;justify-content:center;position:relative;
  background:radial-gradient(circle at 50% 30%,#ffffff,#e7e7e7);
  border-right:1px solid var(--border);
}
.pub-img-inner{text-align:center;display:flex;flex-direction:column;align-items:center;justify-content:center;padding:1.2rem}
.pub-img-type{font-family:var(--font-mono);font-size:.82rem;color:#00405a;letter-spacing:1px;text-transform:uppercase;margin-top:.4rem}
.pub-icon-file{width:8rem;height:4.6rem;object-fit:contain;display:block;filter:drop-shadow(0 3px 8px rgba(0,0,0,.18))}
.pub-body{padding:1.7rem}
.pub-type-badge{
  display:inline-block;background:var(--tint);border:1px solid var(--border-strong);
  border-radius:50px;padding:3px 12px;font-size:.68rem;font-family:var(--font-mono);
  color:var(--accent-hover);margin-bottom:.9rem;letter-spacing:.5px;
}
.pub-title{font-family:var(--font-display);font-weight:600;font-size:1.06rem;line-height:1.4;margin-bottom:.6rem;color:var(--text)}
.pub-authors{font-size:.83rem;color:var(--text2);margin-bottom:.5rem;line-height:1.55}
.pub-authors b{color:var(--accent-hover);font-weight:600}
.pub-citation{
  font-size:.83rem;color:var(--text2);line-height:1.65;
  padding:.85rem 1rem;background:var(--citation-bg);
  border-left:2px solid var(--accent-hover);border-radius:0 8px 8px 0;
}
.pub-citation .cit-label{font-family:var(--font-mono);font-size:.68rem;color:var(--accent-hover);text-transform:uppercase;letter-spacing:1px;display:block;margin-bottom:.4rem}
.pub-citation em{color:var(--text);font-style:italic;font-weight:500}
.pub-meta{display:flex;flex-wrap:wrap;gap:.6rem 1.2rem;margin-top:.9rem}
.pub-meta-item{display:flex;align-items:center;gap:6px;font-size:.76rem;font-family:var(--font-mono);color:var(--text3)}
.pub-meta-item .lbl{color:var(--accent-hover);font-weight:500}

/* ===================== CONTACT ===================== */
#contact{max-width:var(--maxw)}
.contact-grid{display:grid;grid-template-columns:1fr 1.1fr;gap:clamp(2rem,5vw,4rem)}
.contact-info{display:flex;flex-direction:column;gap:1rem}
.contact-card{
  background:linear-gradient(160deg,var(--surface),var(--surface2));
  border:1px solid var(--border);border-radius:var(--radius-sm);
  padding:1.2rem 1.3rem;display:flex;align-items:center;gap:1rem;
  transition:all .25s ease;text-decoration:none;color:inherit;
}
.contact-card:hover{border-color:var(--border-strong);transform:translateX(6px);box-shadow:var(--shadow-sm)}
.cc-icon{width:46px;height:46px;border-radius:12px;background:var(--tint);border:1px solid var(--border-strong);display:flex;align-items:center;justify-content:center;color:var(--accent-hover);font-size:1.15rem;flex-shrink:0}
.cc-label{font-size:.72rem;color:var(--text3);font-family:var(--font-mono);letter-spacing:.6px;margin-bottom:.15rem}
.cc-val{font-size:.9rem;font-weight:500;color:var(--text)}

.contact-form{
  display:flex;flex-direction:column;gap:1.1rem;
  background:linear-gradient(160deg,var(--surface),var(--surface2));
  border:1px solid var(--border);border-radius:var(--radius);
  padding:clamp(1.4rem,3vw,2rem);position:relative;overflow:hidden;
}
.contact-form::before{content:"";position:absolute;top:0;left:0;right:0;height:1px;background:var(--grad-line)}
.form-group{display:flex;flex-direction:column;gap:.5rem}
.form-group label{font-size:.78rem;font-weight:500;color:var(--text2);font-family:var(--font-mono)}
.form-group input,.form-group textarea{
  background:var(--bg2);border:1px solid var(--border);border-radius:10px;padding:12px 15px;
  color:var(--text);font-family:var(--font-body);font-size:.9rem;
  outline:none;transition:border-color .2s ease,box-shadow .2s ease;resize:vertical;
}
.form-group input::placeholder,.form-group textarea::placeholder{color:var(--text3)}
.form-group input:focus,.form-group textarea:focus{border-color:var(--accent-hover);box-shadow:0 0 0 3px var(--tint-strong)}
.form-group textarea{min-height:130px}
.submit-btn{margin-top:.3rem}

/* ===================== FOOTER ===================== */
footer{background:var(--bg2);border-top:1px solid var(--border);padding:2.4rem 5%;text-align:center}
.footer-text{font-size:.82rem;color:var(--text3);font-family:var(--font-mono)}
.footer-text span{background:var(--grad-accent);-webkit-background-clip:text;background-clip:text;-webkit-text-fill-color:transparent;font-weight:500}

/* ===================== REVEAL ===================== */
.fade-in{opacity:0;transform:translateY(28px);transition:opacity .7s cubic-bezier(.4,0,.2,1),transform .7s cubic-bezier(.4,0,.2,1)}
.fade-in.visible{opacity:1;transform:none}

/* ===================== RESPONSIVE ===================== */
@media(max-width:900px){
  :root{--nav-h:64px}
  .nav-links,.nav-right .theme-toggle{display:none}
  .hamburger{display:flex}
  .theme-toggle-mobile{display:flex;align-items:center;gap:8px;cursor:pointer;border:1px solid var(--border);border-radius:50px;padding:8px 15px;width:fit-content;font-size:.8rem;color:var(--text2);background:var(--surface);font-family:var(--font-mono);margin-top:.6rem}
  .social-float{display:none}
  .hero-inner{grid-template-columns:1fr;gap:2.6rem}
  .hero-left{order:2}
  .hero-right{order:1}
  .hero-card{max-width:400px;margin:0 auto}
  .hc-avatar-wrap{width:180px;height:180px}
  .about-grid,.contact-grid{grid-template-columns:1fr}
  .pub-card{grid-template-columns:1fr}
  .pub-img{min-height:130px;border-right:none;border-bottom:1px solid var(--border)}
}
@media(max-width:600px){
  .about-highlights{grid-template-columns:1fr}
  .hero-stats{gap:1.6rem}
  .hero-cta{width:100%}
  .btn-primary,.btn-outline{flex:1;min-width:0}
  .skills-grid{grid-template-columns:repeat(auto-fill,minmax(118px,1fr))}
  .services-grid{grid-template-columns:1fr}
  .exp-header{align-items:flex-start}
}

/* ===================== REDUCED MOTION ===================== */
@media(prefers-reduced-motion:reduce){
  *,*::before,*::after{animation-duration:.001ms!important;animation-iteration-count:1!important;transition-duration:.001ms!important;scroll-behavior:auto!important}
  .fade-in{opacity:1;transform:none}
  .hero-neural{display:none}
}