/* ============================================================
   HEIN.DEV — Design System v3 "Emerald Glass"
   Modern · Layered · Fluid · Accessible
   ============================================================ */

:root {
    /* surfaces */
    --bg: #05080a;
    --bg-soft: #0a1210;
    --card: rgba(255, 255, 255, 0.035);
    --card-hover: rgba(255, 255, 255, 0.06);
    --border: rgba(160, 200, 180, 0.12);
    --border-bright: rgba(160, 220, 195, 0.3);

    /* text */
    --text: #8fa3ad;
    --heading: #eef6f2;
    --muted: #5c6f6a;

    /* brand */
    --accent: #34d399;
    --accent-2: #2dd4bf;
    --gradient: linear-gradient(120deg, #34d399 0%, #2dd4bf 55%, #38bdf8 120%);
    --glow: rgba(16, 185, 129, 0.16);
    --glow-strong: rgba(52, 211, 153, 0.3);

    /* elevation */
    --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.25);
    --shadow-md: 0 10px 30px rgba(0, 0, 0, 0.35);
    --shadow-lg: 0 24px 60px rgba(0, 0, 0, 0.5);

    /* geometry */
    --nav-h: 84px;
    --radius-sm: 12px;
    --radius: 18px;
    --radius-lg: 24px;
    --ease: cubic-bezier(0.16, 1, 0.3, 1);
    --bounce: cubic-bezier(0.34, 1.56, 0.64, 1);

    /* type */
    --font-head: 'Outfit', sans-serif;
    --font-body: 'Inter', sans-serif;
    --font-mono: 'JetBrains Mono', monospace;

    color-scheme: dark;
}

@property --angle {
    syntax: '<angle>';
    initial-value: 0deg;
    inherits: false;
}

/* ---------- reset & base ---------- */
* { margin: 0; padding: 0; box-sizing: border-box; }

html {
    scroll-behavior: smooth;
    scroll-padding-top: calc(var(--nav-h) + 20px);
    color-scheme: dark;
}

body {
    background: var(--bg);
    color: var(--text);
    font-family: var(--font-body);
    font-size: 16px;
    line-height: 1.7;
    overflow-x: hidden;
    -webkit-font-smoothing: antialiased;
    text-rendering: optimizeLegibility;
}

h1, h2, h3, h4 { font-family: var(--font-head); color: var(--heading); }

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

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

::selection { background: rgba(52, 211, 153, 0.3); color: #fff; }

::-webkit-scrollbar { width: 10px; height: 8px; }
::-webkit-scrollbar-track { background: var(--bg); }
::-webkit-scrollbar-thumb {
    background: #1c2b26;
    border-radius: 99px;
    border: 2px solid var(--bg);
}
::-webkit-scrollbar-thumb:hover { background: #2a423a; }

/* ---------- ambient background ---------- */
.bg-decoration { position: fixed; inset: 0; z-index: -1; overflow: hidden; pointer-events: none; }

.orb { position: absolute; border-radius: 50%; filter: blur(130px); opacity: 0.3; }

.orb-1 {
    width: 560px; height: 560px;
    top: -180px; right: -140px;
    background: radial-gradient(circle, rgba(52, 211, 153, 0.5), transparent 70%);
    animation: drift 20s ease-in-out infinite;
}

.orb-2 {
    width: 480px; height: 480px;
    bottom: -160px; left: -140px;
    background: radial-gradient(circle, rgba(45, 212, 191, 0.4), transparent 70%);
    animation: drift 26s ease-in-out infinite reverse;
}

.orb-3 {
    width: 360px; height: 360px;
    top: 42%; left: 58%;
    background: radial-gradient(circle, rgba(56, 189, 248, 0.22), transparent 70%);
    opacity: 0.2;
    animation: drift 30s ease-in-out infinite;
}

@keyframes drift {
    0%, 100% { transform: translate(0, 0) scale(1); }
    33%      { transform: translate(-60px, 45px) scale(1.1); }
    66%      { transform: translate(45px, -35px) scale(0.94); }
}

.grid-overlay {
    position: absolute;
    inset: 0;
    background-image:
        linear-gradient(rgba(148, 200, 180, 0.035) 1px, transparent 1px),
        linear-gradient(90deg, rgba(148, 200, 180, 0.035) 1px, transparent 1px);
    background-size: 54px 54px;
    mask-image: radial-gradient(ellipse 90% 60% at 70% 0%, black 20%, transparent 75%);
    -webkit-mask-image: radial-gradient(ellipse 90% 60% at 70% 0%, black 20%, transparent 75%);
}

/* ---------- scroll progress ---------- */
.scroll-progress {
    position: fixed;
    top: 0; left: 0;
    height: 3px;
    width: 0%;
    background: var(--gradient);
    box-shadow: 0 0 12px var(--glow-strong);
    z-index: 2000;
    transition: width 0.1s linear;
}

/* ---------- floating navbar ---------- */
.navbar {
    position: fixed;
    top: 14px;
    left: 50%;
    transform: translateX(-50%);
    width: min(1180px, calc(100% - 28px));
    height: 62px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 1rem;
    padding: 0 10px 0 24px;
    background: rgba(10, 16, 14, 0.72);
    backdrop-filter: blur(18px);
    -webkit-backdrop-filter: blur(18px);
    border: 1px solid var(--border);
    border-radius: 999px;
    z-index: 1000;
    transition: all 0.4s var(--ease);
}

.navbar.scrolled {
    height: 56px;
    background: rgba(8, 13, 11, 0.88);
    border-color: var(--border-bright);
    box-shadow: 0 14px 40px rgba(0, 0, 0, 0.45), 0 0 0 1px rgba(52, 211, 153, 0.06);
}

.logo {
    font-family: var(--font-head);
    font-size: 1.25rem;
    font-weight: 700;
    letter-spacing: -0.4px;
    color: var(--heading);
    text-decoration: none;
    transition: transform 0.25s var(--ease);
}

.logo:hover { transform: translateY(-2px); }

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

.nav-links {
    display: flex;
    align-items: center;
    gap: 0.35rem;
    list-style: none;
}

.nav-link {
    position: relative;
    padding: 0.5rem 0.95rem;
    border-radius: 999px;
    color: var(--text);
    text-decoration: none;
    font-size: 0.88rem;
    font-weight: 600;
    transition: all 0.25s var(--ease);
}

.nav-link:hover { color: var(--heading); background: var(--card-hover); }

.nav-link.active {
    color: var(--accent);
    background: rgba(52, 211, 153, 0.1);
}

.btn-nav {
    margin-left: 0.5rem;
    padding: 0.55rem 1.35rem !important;
    border-radius: 999px !important;
    border: 1.5px solid var(--accent);
    color: var(--accent) !important;
    font-weight: 700 !important;
    background: transparent;
    transition: all 0.25s var(--ease) !important;
}

.btn-nav:hover {
    background: var(--accent) !important;
    color: #04120c !important;
    box-shadow: 0 8px 24px var(--glow-strong);
    transform: translateY(-2px);
}

/* theme + hamburger */
.theme-toggle {
    width: 40px; height: 40px;
    display: grid; place-items: center;
    border-radius: 50%;
    background: var(--card);
    border: 1px solid var(--border);
    color: var(--heading);
    font-size: 0.95rem;
    cursor: pointer;
    transition: all 0.3s var(--ease);
    flex-shrink: 0;
}

.theme-toggle:hover {
    border-color: var(--accent-2);
    transform: rotate(-12deg) scale(1.06);
    box-shadow: 0 0 18px rgba(45, 212, 191, 0.3);
}

body.light-mode .theme-toggle i { color: #059669; }

.menu-toggle {
    display: none;
    background: var(--card);
    border: 1px solid var(--border);
    border-radius: 12px;
    cursor: pointer;
    padding: 0.55rem 0.65rem;
    z-index: 1001;
}

.menu-toggle .bar {
    display: block;
    width: 22px; height: 2px;
    margin: 5px auto;
    background: var(--heading);
    border-radius: 2px;
    transition: all 0.3s var(--bounce);
}

.menu-toggle.active .bar:nth-child(1) { transform: translateY(7px) rotate(45deg); }
.menu-toggle.active .bar:nth-child(2) { opacity: 0; transform: scaleX(0.4); }
.menu-toggle.active .bar:nth-child(3) { transform: translateY(-7px) rotate(-45deg); }

/* ---------- buttons ---------- */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 0.6rem;
    padding: 0.9rem 1.9rem;
    border-radius: 14px;
    border: none;
    font-family: var(--font-body);
    font-weight: 700;
    font-size: 0.94rem;
    text-decoration: none;
    cursor: pointer;
    transition: all 0.3s var(--ease);
}

.primary-btn {
    background: var(--gradient);
    color: #04120c;
    box-shadow: 0 10px 28px var(--glow-strong);
}

.primary-btn:hover {
    transform: translateY(-3px);
    box-shadow: 0 16px 38px var(--glow-strong);
}

.ghost-btn {
    background: var(--card);
    color: var(--accent);
    border: 1.5px solid rgba(52, 211, 153, 0.35);
    backdrop-filter: blur(8px);
}

.ghost-btn:hover {
    background: var(--glow);
    border-color: var(--accent);
    transform: translateY(-3px);
}

/* ---------- hero ---------- */
.hero {
    position: relative;
    min-height: 100svh;
    display: grid;
    grid-template-columns: 1.12fr 0.88fr;
    align-items: center;
    gap: 4rem;
    max-width: 1240px;
    margin: 0 auto;
    padding: calc(var(--nav-h) + 2.5rem) 2rem 4rem;
}

.greeting {
    display: inline-flex;
    align-items: center;
    gap: 0.6rem;
    font-family: var(--font-mono);
    font-size: 0.82rem;
    font-weight: 600;
    letter-spacing: 2.5px;
    text-transform: uppercase;
    color: var(--accent);
    margin-bottom: 1.2rem;
}

.greeting::before {
    content: "";
    width: 34px;
    height: 1.5px;
    background: var(--accent);
    border-radius: 2px;
}

.hero h1 {
    font-size: clamp(2.7rem, 6.5vw, 4.4rem);
    font-weight: 800;
    line-height: 1.05;
    letter-spacing: -2px;
    margin-bottom: 0.4rem;
}

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

.typed-line {
    font-family: var(--font-head);
    font-size: clamp(1.25rem, 3vw, 1.8rem);
    font-weight: 600;
    color: var(--dim, #b8c8d4);
    margin: 0.6rem 0 1.5rem;
    min-height: 1.5em;
    letter-spacing: -0.3px;
}

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

.type-cursor {
    display: inline-block;
    width: 3px;
    height: 1.05em;
    margin-left: 5px;
    vertical-align: text-bottom;
    background: var(--accent);
    border-radius: 3px;
    animation: blink 0.9s step-end infinite;
}

@keyframes blink { 50% { opacity: 0; } }

.hero-description {
    max-width: 560px;
    font-size: 1.04rem;
    margin-bottom: 2.3rem;
}

.hero-buttons { display: flex; gap: 0.9rem; flex-wrap: wrap; }

.hero-socials { display: flex; gap: 0.8rem; margin-top: 2.4rem; }

.hero-socials a {
    width: 46px; height: 46px;
    display: grid; place-items: center;
    border-radius: 14px;
    background: var(--card);
    border: 1px solid var(--border);
    color: var(--text);
    font-size: 1.08rem;
    transition: all 0.3s var(--ease);
}

.hero-socials a:hover {
    color: var(--accent);
    border-color: var(--accent);
    transform: translateY(-4px) rotate(-4deg);
    box-shadow: 0 10px 24px var(--glow);
}

/* ---------- photo ---------- */
.hero-image { display: grid; place-items: center; }

.photo-frame {
    position: relative;
    width: min(320px, 100%);
    padding: 5px;
    border-radius: 28px;
}

.photo-frame::before,
.photo-frame::after {
    content: "";
    position: absolute;
    inset: -3px;
    border-radius: 30px;
    background: conic-gradient(from var(--angle),
        transparent 0deg,
        var(--accent) 60deg,
        var(--accent-2) 140deg,
        #38bdf8 200deg,
        transparent 260deg);
    animation: rotate-border 7s linear infinite;
    z-index: 0;
}

.photo-frame::after { filter: blur(26px); opacity: 0.4; }

@keyframes rotate-border { to { --angle: 360deg; } }

.photo-inner {
    position: relative;
    z-index: 1;
    border-radius: 24px;
    overflow: hidden;
    background: var(--bg-soft);
}

.photo-inner img {
    width: 100%;
    height: 390px;
    object-fit: cover;
    object-position: center top;
    transition: transform 0.7s var(--ease);
}

.photo-frame:hover .photo-inner img { transform: scale(1.05); }

.photo-badge {
    position: absolute;
    top: 20px; right: -16px;
    z-index: 3;
    display: flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.5rem 1rem;
    border-radius: 999px;
    background: rgba(8, 14, 12, 0.92);
    backdrop-filter: blur(14px);
    -webkit-backdrop-filter: blur(14px);
    border: 1px solid rgba(52, 211, 153, 0.45);
    color: var(--heading);
    font-family: var(--font-mono);
    font-size: 0.7rem;
    font-weight: 600;
    letter-spacing: 0.4px;
    box-shadow: 0 14px 34px rgba(0, 0, 0, 0.5);
    animation: floaty 5s ease-in-out infinite 1.6s;
}

.pulse-dot {
    width: 8px; height: 8px;
    border-radius: 50%;
    background: var(--accent);
    flex-shrink: 0;
    animation: pulse 2s infinite;
}

@keyframes pulse {
    0%   { box-shadow: 0 0 0 0 rgba(52, 211, 153, 0.5); }
    70%  { box-shadow: 0 0 0 9px rgba(52, 211, 153, 0); }
    100% { box-shadow: 0 0 0 0 rgba(52, 211, 153, 0); }
}

.float-chip {
    position: absolute;
    z-index: 2;
    display: flex;
    align-items: center;
    gap: 0.45rem;
    padding: 0.5rem 0.9rem;
    border-radius: 12px;
    background: rgba(8, 14, 12, 0.88);
    backdrop-filter: blur(14px);
    -webkit-backdrop-filter: blur(14px);
    border: 1px solid var(--border-bright);
    color: var(--heading);
    font-family: var(--font-mono);
    font-size: 0.74rem;
    font-weight: 600;
    letter-spacing: 0.4px;
    box-shadow: 0 14px 34px rgba(0, 0, 0, 0.45);
    animation: floaty 5.5s ease-in-out infinite;
}

.chip-1 { top: 9%; left: -16%; }
.chip-1 i { color: #f97316; }
.chip-2 { bottom: 24%; right: -15%; animation-delay: 1.3s; }
.chip-2 i { color: #38bdf8; }
.chip-3 { bottom: -4%; left: -9%; animation-delay: 2.6s; }
.chip-3 i { color: #facc15; }

@keyframes floaty {
    0%, 100% { transform: translateY(0); }
    50%      { transform: translateY(-13px); }
}

/* ---------- scroll hint ---------- */
.scroll-hint {
    position: absolute;
    left: 50%;
    bottom: 1.8rem;
    transform: translateX(-50%);
    opacity: 0.6;
    transition: opacity 0.3s;
}

.scroll-hint:hover { opacity: 1; }

.mouse {
    display: block;
    width: 25px; height: 40px;
    border: 2px solid var(--muted, #5c6f6a);
    border-radius: 14px;
    position: relative;
}

.wheel {
    position: absolute;
    top: 7px; left: 50%;
    width: 4px; height: 8px;
    margin-left: -2px;
    border-radius: 4px;
    background: var(--accent);
    animation: wheel 1.8s ease-in-out infinite;
}

@keyframes wheel {
    0%   { transform: translateY(0); opacity: 1; }
    70%  { transform: translateY(12px); opacity: 0; }
    100% { transform: translateY(0); opacity: 0; }
}

/* ---------- sections ---------- */
.section {
    max-width: 1240px;
    margin: 0 auto;
    padding: 6.5rem 2rem;
    scroll-margin-top: calc(var(--nav-h) + 10px);
}

.section-head {
    display: flex;
    align-items: center;
    gap: 1rem;
    margin-bottom: 3rem;
}

.eyebrow {
    font-family: var(--font-mono);
    font-size: 0.95rem;
    font-weight: 700;
    background: var(--gradient);
    -webkit-background-clip: text;
    background-clip: text;
    -webkit-text-fill-color: transparent;
}

.section-title {
    font-size: clamp(1.75rem, 3.5vw, 2.3rem);
    font-weight: 800;
    letter-spacing: -0.8px;
    white-space: nowrap;
}

.section-head::after {
    content: "";
    flex: 1;
    height: 1px;
    max-width: 300px;
    background: linear-gradient(90deg, var(--border-bright), transparent);
    margin-left: 0.4rem;
}

/* ---------- about ---------- */
.about-grid {
    display: grid;
    grid-template-columns: 1.12fr 0.88fr;
    gap: 4rem;
    align-items: center;
}

.about-text p { font-size: 1.02rem; margin-bottom: 1.2rem; }

.info-list {
    display: grid;
    gap: 0.85rem;
    margin: 1.8rem 0 2.2rem;
    padding: 1.4rem 1.5rem;
    background: var(--card);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    backdrop-filter: blur(8px);
}

.info-list div { display: flex; align-items: baseline; gap: 0.6rem; font-size: 0.94rem; }
.info-list strong { color: var(--heading); font-weight: 600; }

.info-list i {
    color: var(--accent);
    font-size: 0.88rem;
    margin-top: 0.3em;
    flex-shrink: 0;
}

.stats-row {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 0.9rem;
}

.stat {
    padding: 1.15rem 0.7rem;
    text-align: center;
    background: var(--card);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    transition: all 0.3s var(--ease);
}

.stat:hover {
    transform: translateY(-4px);
    border-color: rgba(52, 211, 153, 0.5);
    box-shadow: 0 12px 30px var(--glow);
}

.stat-num {
    display: block;
    font-family: var(--font-head);
    font-size: 1.8rem;
    font-weight: 800;
    background: var(--gradient);
    -webkit-background-clip: text;
    background-clip: text;
    -webkit-text-fill-color: transparent;
}

.stat-label {
    font-family: var(--font-mono);
    font-size: 0.63rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 1.2px;
}

.about-visual { display: grid; place-items: center; }

/* ---------- skills ---------- */
.skills-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(255px, 1fr));
    gap: 1.3rem;
}

.skill-card {
    position: relative;
    padding: 1.8rem;
    background: var(--card);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    overflow: hidden;
    transition: transform 0.35s var(--ease), border-color 0.35s, box-shadow 0.35s, background 0.35s;
}

.skill-card::before {
    content: "";
    position: absolute;
    top: 0; left: 0;
    width: 100%; height: 3px;
    background: var(--gradient);
    transform: scaleX(0);
    transform-origin: left;
    transition: transform 0.45s var(--ease);
}

.skill-card:hover {
    transform: translateY(-6px);
    background: var(--card-hover);
    border-color: var(--border-bright);
    box-shadow: var(--shadow-md);
}

.skill-card:hover::before { transform: scaleX(1); }

.skill-card i {
    font-size: 2rem;
    margin-bottom: 1.1rem;
    background: var(--gradient);
    -webkit-background-clip: text;
    background-clip: text;
    -webkit-text-fill-color: transparent;
}

.skill-card h3 { font-size: 1.08rem; font-weight: 700; margin-bottom: 0.45rem; letter-spacing: -0.2px; }
.skill-card p { font-size: 0.91rem; }

/* ---------- project filters ---------- */
.project-filters {
    display: flex;
    flex-wrap: wrap;
    gap: 8px;
    margin-bottom: 2rem;
}

.filter-chip {
    padding: 9px 17px;
    border-radius: 999px;
    background: var(--card);
    border: 1.5px solid var(--border);
    color: var(--text);
    font-family: inherit;
    font-size: 0.83rem;
    font-weight: 700;
    cursor: pointer;
    transition: all 0.22s var(--ease);
}

.filter-chip:hover {
    color: var(--heading);
    border-color: var(--border-bright);
    transform: translateY(-2px);
}

.filter-chip.active {
    background: var(--gradient);
    border-color: transparent;
    color: #04120c;
    box-shadow: 0 6px 20px var(--glow-strong);
}

.filter-chip .cnt {
    font-size: 0.64rem;
    font-weight: 800;
    background: rgba(4, 18, 12, 0.18);
    padding: 2px 7px;
    border-radius: 999px;
    margin-left: 3px;
}

.filter-chip:not(.active) .cnt { background: rgba(255, 255, 255, 0.07); }

.project-card[hidden] { display: none; }

/* ---------- projects ---------- */
.projects-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(310px, 1fr));
    gap: 1.3rem;
}

.project-card {
    position: relative;
    display: flex;
    flex-direction: column;
    padding: 1.8rem;
    background: var(--card);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    overflow: hidden;
    transition: transform 0.35s var(--ease), border-color 0.35s, box-shadow 0.35s, background 0.35s;
}

.project-card::before {
    content: "";
    position: absolute;
    inset: 0;
    border-radius: inherit;
    padding: 1.5px;
    background: var(--gradient);
    -webkit-mask: linear-gradient(#fff 0 0) content-box, linear-gradient(#fff 0 0);
    mask: linear-gradient(#fff 0 0) content-box, linear-gradient(#fff 0 0);
    -webkit-mask-composite: xor;
    mask-composite: exclude;
    opacity: 0;
    transition: opacity 0.35s ease;
    pointer-events: none;
}

.project-card:hover {
    transform: translateY(-7px);
    background: var(--card-hover);
    border-color: transparent;
    box-shadow: var(--shadow-lg), 0 0 40px var(--glow);
}

.project-card:hover::before,
.project-card.highlight::before { opacity: 1; }

.project-top {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 1.3rem;
}

.project-num {
    font-family: var(--font-mono);
    font-size: 0.82rem;
    font-weight: 700;
    background: var(--gradient);
    -webkit-background-clip: text;
    background-clip: text;
    -webkit-text-fill-color: transparent;
}

.project-folder i { font-size: 1.5rem; color: var(--accent); opacity: 0.9; }

.project-card h3 {
    font-size: 1.22rem;
    font-weight: 700;
    letter-spacing: -0.3px;
    margin-bottom: 0.6rem;
    transition: color 0.25s ease;
}

.project-card:hover h3 { color: var(--accent); }

.project-card > p { font-size: 0.92rem; flex-grow: 1; }

.tech-stack {
    display: flex;
    flex-wrap: wrap;
    gap: 0.45rem;
    list-style: none;
    font-family: var(--font-mono);
    font-size: 0.68rem;
    font-weight: 600;
    margin: 1.3rem 0 1.2rem;
}

.tech-stack li {
    color: var(--accent);
    background: rgba(52, 211, 153, 0.07);
    border: 1px solid rgba(52, 211, 153, 0.22);
    padding: 0.28rem 0.7rem;
    border-radius: 999px;
}

.project-links a {
    color: var(--heading);
    text-decoration: none;
    font-weight: 700;
    font-size: 0.87rem;
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    transition: color 0.25s, gap 0.25s;
}

.project-links a:hover { color: var(--accent); gap: 0.8rem; }

/* ---------- timeline ---------- */
.timeline {
    position: relative;
    max-width: 800px;
    margin: 0 auto;
    display: flex;
    flex-direction: column;
    gap: 1.6rem;
}

.timeline::before {
    content: "";
    position: absolute;
    left: 25px;
    top: 12px;
    bottom: 12px;
    width: 2px;
    background: linear-gradient(180deg, var(--accent), var(--accent-2) 60%, transparent);
    opacity: 0.35;
}

.timeline-item { position: relative; padding-left: 72px; }

.timeline-icon {
    position: absolute;
    left: 0; top: 4px;
    width: 50px; height: 50px;
    border-radius: 15px;
    display: grid; place-items: center;
    font-size: 1.15rem;
    color: var(--accent);
    background: var(--bg-soft);
    border: 1px solid var(--border-bright);
    box-shadow: 0 0 22px var(--glow);
    z-index: 1;
}

.timeline-card {
    background: var(--card);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    padding: 1.4rem 1.6rem;
    transition: transform 0.3s var(--ease), border-color 0.3s, background 0.3s;
}

.timeline-card:hover {
    transform: translateX(6px);
    background: var(--card-hover);
    border-color: var(--border-bright);
}

.timeline-item h3 { font-size: 1.12rem; font-weight: 700; letter-spacing: -0.2px; }

.timeline-subtitle {
    color: var(--accent);
    font-weight: 600;
    font-size: 0.83rem;
    margin: 0.25rem 0 0.5rem;
}

.timeline-card p:last-child { font-size: 0.92rem; }

.timeline-card p.cert-serial {
    margin-top: 0.65rem;
    font-family: var(--font-mono);
    font-size: 0.68rem;
    font-weight: 600;
    letter-spacing: 1px;
    color: var(--muted, #5c6f6a);
}

/* ---------- contact ---------- */
.contact-sub {
    max-width: 620px;
    font-size: 1.02rem;
    margin: -1.4rem 0 2.4rem;
}

.contact-container {
    display: grid;
    grid-template-columns: 0.9fr 1.1fr;
    gap: 2.6rem;
    align-items: start;
}

.contact-info { display: flex; flex-direction: column; gap: 0.9rem; }

.contact-item {
    display: flex;
    align-items: center;
    gap: 1.05rem;
    padding: 1.1rem 1.25rem;
    background: var(--card);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    text-decoration: none;
    color: inherit;
    transition: all 0.3s var(--ease);
}

.contact-item:not(.static):hover {
    transform: translateX(6px);
    border-color: rgba(52, 211, 153, 0.5);
    background: var(--card-hover);
}

.contact-item > i:first-child {
    font-size: 1.1rem;
    color: var(--accent);
    width: 46px; height: 46px;
    display: grid; place-items: center;
    background: rgba(52, 211, 153, 0.1);
    border-radius: 13px;
    flex-shrink: 0;
}

.contact-item h4 {
    font-family: var(--font-mono);
    font-size: 0.66rem;
    color: var(--dim, var(--text));
    text-transform: uppercase;
    letter-spacing: 1.6px;
    font-weight: 600;
}

.contact-item p {
    color: var(--heading);
    font-size: 0.96rem;
    font-weight: 500;
    word-break: break-word;
}

.copy-btn {
    margin-left: auto;
    width: 36px; height: 36px;
    border-radius: 10px;
    background: rgba(52, 211, 153, 0.07);
    border: 1px solid var(--border);
    color: var(--text);
    font-size: 0.84rem;
    cursor: pointer;
    display: grid; place-items: center;
    flex-shrink: 0;
    transition: all 0.22s var(--ease);
}

.copy-btn:hover {
    color: var(--accent);
    border-color: var(--accent);
    transform: translateY(-2px) scale(1.06);
}

.copy-btn.copied { color: var(--ok, #34d399); border-color: var(--ok, #34d399); }

.item-arrow {
    font-size: 0.78rem;
    color: var(--text);
    opacity: 0;
    transform: translateX(-6px);
    transition: all 0.3s ease;
}

.contact-item:not(.static):hover .item-arrow {
    opacity: 1;
    transform: none;
    color: var(--accent);
}

.contact-note {
    display: flex;
    align-items: center;
    gap: 0.7rem;
    padding: 0.9rem 1.25rem;
    font-size: 0.87rem;
    font-weight: 600;
    color: var(--accent);
    background: rgba(52, 211, 153, 0.06);
    border: 1px solid rgba(52, 211, 153, 0.22);
    border-radius: var(--radius);
}

.contact-form {
    display: flex;
    flex-direction: column;
    gap: 1.05rem;
    padding: 1.8rem;
    background: var(--card);
    border: 1px solid var(--border);
    border-radius: var(--radius);
}

.form-row { display: grid; grid-template-columns: 1fr 1fr; gap: 1.05rem; }

.contact-form input,
.contact-form textarea {
    width: 100%;
    background: var(--bg-soft);
    border: 1px solid var(--border);
    padding: 0.9rem 1.1rem;
    font-family: inherit;
    font-size: 0.93rem;
    color: var(--heading);
    border-radius: 12px;
    outline: none;
    resize: vertical;
    transition: all 0.25s ease;
}

.contact-form input::placeholder,
.contact-form textarea::placeholder { color: var(--muted, #5c6f6a); }

.contact-form input:focus,
.contact-form textarea:focus {
    border-color: var(--accent);
    box-shadow: 0 0 0 4px var(--glow);
}

.contact-form textarea { min-height: 130px; }

.submit-btn { align-self: flex-start; }

.submit-btn:disabled { opacity: 0.55; cursor: not-allowed; transform: none !important; }

/* ---------- footer ---------- */
footer {
    text-align: center;
    padding: 3.5rem 2rem 2.5rem;
    border-top: 1px solid var(--border);
}

.footer-logo {
    font-family: var(--font-head);
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--heading);
    text-decoration: none;
}

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

.footer-tagline { margin: 0.4rem 0 1.4rem; font-size: 0.9rem; }

.footer-socials {
    display: flex;
    justify-content: center;
    gap: 0.8rem;
    margin-bottom: 1.6rem;
}

.footer-socials a {
    width: 42px; height: 42px;
    display: grid; place-items: center;
    border-radius: 13px;
    background: var(--card);
    border: 1px solid var(--border);
    color: var(--text);
    font-size: 1.02rem;
    transition: all 0.3s var(--ease);
}

.footer-socials a:hover {
    color: var(--accent);
    border-color: var(--accent);
    transform: translateY(-4px);
    box-shadow: 0 8px 22px var(--glow);
}

.footer-copy { font-size: 0.8rem; color: var(--muted, #5c6f6a); }

/* ---------- scroll top ---------- */
.scroll-top-btn {
    position: fixed;
    bottom: 1.8rem;
    right: 1.8rem;
    width: 46px; height: 46px;
    border-radius: 14px;
    background: rgba(10, 16, 14, 0.9);
    backdrop-filter: blur(12px);
    border: 1px solid var(--border-bright);
    color: var(--heading);
    cursor: pointer;
    display: grid; place-items: center;
    box-shadow: var(--shadow-md);
    opacity: 0;
    visibility: hidden;
    transform: translateY(14px);
    transition: all 0.3s var(--ease);
    z-index: 999;
}

.scroll-top-btn.visible { opacity: 1; visibility: visible; transform: none; }

.scroll-top-btn:hover {
    background: var(--gradient);
    color: #04120c;
    border-color: transparent;
    box-shadow: 0 12px 30px var(--glow-strong);
}

/* ---------- toasts ---------- */
.toast-container {
    position: fixed;
    top: calc(var(--nav-h) + 8px);
    right: 1.6rem;
    z-index: 2000;
    display: flex;
    flex-direction: column;
    gap: 0.7rem;
    pointer-events: none;
}

.toast {
    pointer-events: auto;
    min-width: 270px;
    max-width: 380px;
    padding: 0.95rem 1.2rem;
    border-radius: 14px;
    background: rgba(10, 18, 16, 0.94);
    backdrop-filter: blur(16px);
    border: 1px solid var(--border-bright);
    box-shadow: var(--shadow-lg);
    display: flex;
    align-items: center;
    gap: 0.75rem;
    font-weight: 600;
    font-size: 0.89rem;
    color: var(--heading);
    transform: translateX(30px);
    opacity: 0;
    transition: all 0.4s var(--ease);
}

.toast.show { transform: none; opacity: 1; }
.toast-success i { color: var(--accent); }
.toast-error i { color: #f87171; }

/* ---------- reveal ---------- */
.reveal {
    opacity: 0;
    transform: translateY(26px);
    transition: opacity 0.7s var(--ease), transform 0.7s var(--ease);
}

.reveal.visible { opacity: 1; transform: none; }

/* ============================================================
   ISOMETRIC STACK
   ============================================================ */
.iso-container {
    perspective: 1200px;
    width: 100%;
    max-width: 480px;
    height: 400px;
    display: grid;
    place-items: center;
    cursor: grab;
}

.iso-stack {
    position: relative;
    width: 100%;
    height: 100%;
    transform-style: preserve-3d;
    transform: rotateX(55deg) rotateZ(-45deg);
    transition: transform 0.1s ease-out;
}

.iso-layer {
    position: absolute;
    border-radius: 18px;
    display: grid;
    place-items: center;
    font-family: var(--font-head);
    font-weight: 600;
}

.layer-main {
    width: 225px; height: 225px;
    top: 87px; left: 87px;
    background: linear-gradient(135deg, rgba(10, 18, 15, 0.94), rgba(5, 8, 10, 0.97));
    border: 1.5px solid rgba(52, 211, 153, 0.55);
    box-shadow: inset 0 0 26px rgba(52, 211, 153, 0.12), 0 30px 60px rgba(0, 0, 0, 0.6);
    transform: translateZ(0);
    animation: floatMain 4s ease-in-out infinite;
}

.layer-title {
    position: absolute;
    bottom: 15px;
    font-family: var(--font-mono);
    font-size: 0.8rem;
    letter-spacing: 1.5px;
    color: rgba(241, 245, 249, 0.55);
}

.iso-inner-badge {
    display: flex;
    align-items: center;
    gap: 8px;
    background: rgba(52, 211, 153, 0.1);
    padding: 10px 17px;
    border-radius: 12px;
    border: 1px solid rgba(52, 211, 153, 0.35);
    color: var(--heading);
    font-size: 0.95rem;
}

.iso-inner-badge i { color: var(--accent); }

.layer-styl {
    width: 225px; height: 225px;
    top: 44px; left: 44px;
    background: rgba(10, 18, 15, 0.42);
    border: 1px solid rgba(45, 212, 191, 0.3);
    transform: translateZ(60px);
    animation: floatStyl 4s ease-in-out infinite 0.3s;
    color: rgba(45, 212, 191, 0.7);
    font-size: 0.8rem;
    letter-spacing: 1.5px;
}

.layer-sass {
    width: 225px; height: 225px;
    top: 2px; left: 2px;
    background: rgba(10, 18, 15, 0.26);
    border: 1px solid var(--border);
    transform: translateZ(120px);
    animation: floatSass 4s ease-in-out infinite 0.6s;
    color: rgba(148, 163, 184, 0.45);
    font-size: 0.8rem;
    letter-spacing: 1.5px;
}

.iso-badge {
    position: absolute;
    width: 60px; height: 60px;
    background: rgba(10, 18, 15, 0.94);
    border: 1.5px solid rgba(52, 211, 153, 0.5);
    border-radius: 15px;
    display: grid; place-items: center;
    font-family: var(--font-mono);
    font-size: 0.68rem;
    font-weight: 700;
    letter-spacing: 0.5px;
    color: var(--heading);
    box-shadow: 0 14px 30px rgba(0, 0, 0, 0.5);
}

.badge-css { top: 292px; left: 20px; transform: translateZ(40px); animation: floatBadge1 4s ease-in-out infinite 0.2s; }
.badge-js  { top: 350px; left: 124px; transform: translateZ(20px); animation: floatBadge2 4s ease-in-out infinite 0.5s; }
.badge-html { top: 272px; left: 330px; transform: translateZ(50px); animation: floatBadge3 4s ease-in-out infinite 0.8s; }

.iso-svg {
    position: absolute;
    inset: 0;
    width: 100%; height: 100%;
    pointer-events: none;
    overflow: visible;
}

.iso-svg line {
    stroke: rgba(52, 211, 153, 0.35);
    stroke-width: 1.5;
    stroke-dasharray: 4 4;
    animation: dashAnimation 20s linear infinite;
}

@keyframes floatMain {
    0%, 100% { transform: translateZ(0) translateY(0); }
    50%      { transform: translateZ(10px) translateY(-6px); }
}
@keyframes floatStyl {
    0%, 100% { transform: translateZ(60px) translateY(0); }
    50%      { transform: translateZ(75px) translateY(-10px); }
}
@keyframes floatSass {
    0%, 100% { transform: translateZ(120px) translateY(0); }
    50%      { transform: translateZ(140px) translateY(-14px); }
}
@keyframes floatBadge1 {
    0%, 100% { transform: translateZ(40px) translateY(0); }
    50%      { transform: translateZ(55px) translateY(-8px); }
}
@keyframes floatBadge2 {
    0%, 100% { transform: translateZ(20px) translateY(0); }
    50%      { transform: translateZ(35px) translateY(-6px); }
}
@keyframes floatBadge3 {
    0%, 100% { transform: translateZ(50px) translateY(0); }
    50%      { transform: translateZ(65px) translateY(-10px); }
}
@keyframes dashAnimation { to { stroke-dashoffset: -100; } }

@media (hover: none) and (pointer: coarse) {
    .iso-container.idle .iso-stack { animation: isoSway 16s ease-in-out infinite alternate; }
}

@keyframes isoSway {
    0%   { transform: rotateX(58deg) rotateZ(-52deg); }
    50%  { transform: rotateX(47deg) rotateZ(-38deg); }
    100% { transform: rotateX(58deg) rotateZ(-52deg); }
}

/* ============================================================
   LIGHT MODE
   ============================================================ */
body.light-mode {
    --bg: #f1f6f3;
    --bg-soft: #ffffff;
    --card: rgba(6, 50, 40, 0.045);
    --card-hover: rgba(6, 50, 40, 0.075);
    --border: rgba(6, 60, 45, 0.13);
    --border-bright: rgba(6, 60, 45, 0.28);
    --text: #476055;
    --heading: #0a1f18;
    --muted: #7d998d;
    --glow: rgba(16, 185, 129, 0.14);
    --glow-strong: rgba(16, 185, 129, 0.3);
    --shadow-md: 0 10px 30px rgba(6, 50, 40, 0.12);
    --shadow-lg: 0 24px 60px rgba(6, 50, 40, 0.16);

    color-scheme: light;
}

body.light-mode ::selection { background: rgba(16, 185, 129, 0.25); }

body.light-mode ::-webkit-scrollbar-track { background: #e6efe9; }
body.light-mode ::-webkit-scrollbar-thumb { background: #b9d4c7; border-color: #e6efe9; }
body.light-mode ::-webkit-scrollbar-thumb:hover { background: #97c2ae; }

body.light-mode .orb { opacity: 0.16; }

body.light-mode .grid-overlay {
    background-image:
        linear-gradient(rgba(4, 78, 56, 0.055) 1px, transparent 1px),
        linear-gradient(90deg, rgba(4, 78, 56, 0.055) 1px, transparent 1px);
}

body.light-mode .navbar { background: rgba(241, 246, 243, 0.75); }
body.light-mode .navbar.scrolled { background: rgba(241, 246, 243, 0.9); box-shadow: var(--shadow-md); }

body.light-mode .nav-links {
    background: rgba(255, 255, 255, 0.97);
    border: 1px solid var(--border);
    border-radius: 18px;
    padding: 0.5rem;
}

body.light-mode .theme-toggle i { color: #059669; }

body.light-mode .primary-btn { color: #fff; }
body.light-mode .scroll-top-btn:hover { color: #fff; }

body.light-mode .toast {
    background: rgba(255, 255, 255, 0.96);
    box-shadow: 0 16px 44px rgba(6, 50, 40, 0.16);
}

body.light-mode .timeline-icon { background: #ffffff; }

body.light-mode .float-chip,
body.light-mode .photo-badge {
    background: rgba(255, 255, 255, 0.93);
    box-shadow: 0 14px 34px rgba(6, 50, 40, 0.14);
}

body.light-mode .photo-inner { background: #e6efe9; }

body.light-mode .scroll-top-btn {
    background: rgba(255, 255, 255, 0.94);
    box-shadow: 0 12px 32px rgba(6, 50, 40, 0.16);
}

body.light-mode footer { border-top-color: var(--border); }

body.light-mode .skill-card::after,
body.light-mode .project-card::after {
    background: radial-gradient(
        260px circle at var(--mx, 50%) var(--my, 50%),
        rgba(16, 185, 129, 0.09),
        transparent 65%
    );
}

body.light-mode .layer-main {
    background: linear-gradient(135deg, rgba(255, 255, 255, 0.96), rgba(230, 239, 233, 0.98));
}
body.light-mode .layer-styl { background: rgba(20, 184, 166, 0.08); }
body.light-mode .layer-sass { background: rgba(70, 100, 88, 0.06); }
body.light-mode .iso-badge { background: #ffffff; }
body.light-mode .iso-inner-badge { background: rgba(16, 185, 129, 0.09); }
body.light-mode .iso-svg line { stroke: rgba(13, 148, 136, 0.4); }

/* ============================================================
   RESPONSIVE
   ============================================================ */
@media (max-width: 1024px) {
    .hero { grid-template-columns: 1fr 0.9fr; gap: 2.5rem; }
    .photo-frame { width: 265px; }
    .photo-inner img { height: 335px; }
    .about-grid { grid-template-columns: 1fr; gap: 2.5rem; }
    .iso-container { height: 360px; }
}

@media (max-width: 768px) {
    :root { --nav-h: 74px; }

    .navbar { width: calc(100% - 20px); top: 10px; padding-left: 18px; }
    .navbar.scrolled { height: 54px; }

    .menu-toggle { display: block; }

    .nav-links {
        position: fixed;
        top: calc(var(--nav-h) + 4px);
        right: 10px;
        width: min(310px, calc(100% - 20px));
        height: auto;
        max-height: calc(100vh - var(--nav-h) - 24px);
        background: rgba(8, 13, 11, 0.97);
        backdrop-filter: blur(22px);
        -webkit-backdrop-filter: blur(22px);
        flex-direction: column;
        align-items: stretch;
        padding: 1.2rem;
        gap: 0.4rem;
        border: 1px solid var(--border-bright);
        border-radius: 22px;
        box-shadow: var(--shadow-lg);
        opacity: 0;
        visibility: hidden;
        transform: translateY(-12px) scale(0.98);
        transition: all 0.35s var(--ease);
    }

    .nav-links.active {
        opacity: 1;
        visibility: visible;
        transform: none;
    }

    .nav-link { padding: 0.8rem 1rem; font-size: 0.98rem; }
    .btn-nav { text-align: center; margin-top: 0.4rem; }

    body.light-mode .nav-links { background: rgba(255, 255, 255, 0.98); }

    .hero {
        grid-template-columns: 1fr;
        text-align: center;
        gap: 3.2rem;
        padding-top: calc(var(--nav-h) + 3rem);
        min-height: auto;
        padding-bottom: 5rem;
    }

    .greeting::before { display: none; }
    .hero-description { margin: 0 auto 2.2rem; }
    .hero-buttons, .hero-socials { justify-content: center; }
    .scroll-hint { display: none; }

    .chip-1 { left: -5%; }
    .chip-2 { right: -5%; }
    .chip-3 { left: 3%; }
    .photo-badge { right: -8px; }

    .section { padding: 4.5rem 1.4rem; }
    .stats-row { grid-template-columns: repeat(2, 1fr); }
    .contact-container { grid-template-columns: 1fr; }
    .form-row { grid-template-columns: 1fr; }

    .toast-container { left: 1rem; right: 1rem; align-items: center; }
    .iso-container { transform: scale(0.8); height: 340px; }
}

@media (max-width: 520px) {
    .hero h1 { letter-spacing: -1px; }

    .float-chip { padding: 0.4rem 0.7rem; font-size: 0.66rem; }
    .chip-1 { left: -2%; }
    .chip-2 { right: -2%; }

    /* JavaScript chip — phone မှာလည်း ပါလာအောင် */
    .chip-3 {
        display: flex;
        left: 4%;
        bottom: -7%;
        animation-delay: 2.4s;
    }

    .photo-badge {
        right: -4px;
        padding: 0.4rem 0.75rem;
        font-size: 0.63rem;
    }

    .photo-frame { width: 235px; }
    .photo-inner img { height: 300px; }

    /* Stats cards — phone မှာ ကျစ်ကျစ်လေး */
    .stats-row { gap: 8px; }
    .stat { padding: 0.85rem 0.5rem; border-radius: 12px; }
    .stat-num { font-size: 1.45rem; }
    .stat-label { font-size: 0.56rem; letter-spacing: 0.4px; }

    .submit-btn { align-self: stretch; }

    .timeline::before { left: 21px; }
    .timeline-item { padding-left: 60px; }
    .timeline-icon { width: 44px; height: 44px; font-size: 1rem; border-radius: 12px; }

    .iso-container { transform: scale(0.62); height: 300px; transform-origin: center; }
}

/* ---------- reduced motion ----------
   System "Reduce Motion" ဖွင့်ထားလျှင်လည်း phone မှာ motion မပျောက်စေရန် —
   transitions/reveals ပဲ ပိတ်ပြီး signature animations (iso sway, floaty
   chips, pulse dot) တွေကို ဆက်လည်ပါစေ။ */
@media (prefers-reduced-motion: reduce) {
    html { scroll-behavior: auto; }
    *, *::before, *::after {
        transition-duration: 0.01ms !important;
    }
    .reveal {
        opacity: 1;
        transform: none;
        transition: none;
    }
    .scroll-hint { display: none; }
}