/* ============================================================ hakan.science — design system Plain CSS, no build step. Theming via CSS variables. Dark mode = (set by inline script + toggle). ============================================================ */ /* Self-hosted Inter (variable font, latin) — no external dependency, so the site looks right even fully offline. */ @font-face { font-family: "Inter"; font-style: normal; font-weight: 100 900; font-display: swap; src: url("../fonts/Inter.woff2") format("woff2"); } :root { /* palette */ --primary: #6366f1; --primary-light: #818cf8; --secondary: #14b8a6; --secondary-light: #2dd4bf; --success: #22c55e; /* surfaces (light) */ --bg: #ffffff; --bg-soft: #f8fafc; --surface: #ffffff; --surface-2: #f1f5f9; --border: #e2e8f0; --text: #0f172a; --text-muted: #475569; --text-faint: #94a3b8; --shadow: 0 1px 3px rgba(15, 23, 42, .08), 0 1px 2px rgba(15, 23, 42, .04); --shadow-lg: 0 10px 30px -10px rgba(15, 23, 42, .18); --maxw: 72rem; --radius: 16px; --nav-h: 4rem; --font: "Inter", system-ui, -apple-system, "Segoe UI", Roboto, Helvetica, Arial, sans-serif; --mono: ui-monospace, "SF Mono", "Cascadia Code", "Roboto Mono", Menlo, Consolas, monospace; } html[data-theme="dark"] { --bg: #0b1120; --bg-soft: #0f172a; --surface: #111a2e; --surface-2: #1a2540; --border: #243049; --text: #e7ecf5; --text-muted: #a7b3c9; --text-faint: #64748b; --shadow: 0 1px 3px rgba(0, 0, 0, .4); --shadow-lg: 0 10px 30px -10px rgba(0, 0, 0, .6); } * { box-sizing: border-box; } html { scroll-behavior: smooth; } body { margin: 0; font-family: var(--font); background: var(--bg); color: var(--text); line-height: 1.6; -webkit-font-smoothing: antialiased; text-rendering: optimizeLegibility; } a { color: inherit; text-decoration: none; } h1, h2, h3, h4 { line-height: 1.2; letter-spacing: -0.02em; } /* ---------- layout helpers ---------- */ .container { max-width: var(--maxw); margin: 0 auto; padding: 0 1.25rem; } .narrow { max-width: 50rem; } /* ---------- top nav ---------- */ .nav { position: fixed; inset: 0 0 auto 0; height: var(--nav-h); z-index: 50; background: color-mix(in srgb, var(--bg) 80%, transparent); backdrop-filter: blur(12px); border-bottom: 1px solid var(--border); } .nav-inner { max-width: var(--maxw); margin: 0 auto; height: 100%; padding: 0 1.25rem; display: flex; align-items: center; justify-content: space-between; gap: 1rem; } .brand { font-weight: 800; font-size: 1.2rem; letter-spacing: -.03em; } .brand .dot { color: var(--primary); } .nav-links { display: flex; align-items: center; gap: .35rem; } .nav-link { padding: .45rem .75rem; border-radius: 10px; font-weight: 600; font-size: .9rem; color: var(--text-muted); transition: .15s; } .nav-link:hover { color: var(--text); background: var(--surface-2); } .icon-btn { display: inline-flex; align-items: center; justify-content: center; width: 2.25rem; height: 2.25rem; border-radius: 10px; cursor: pointer; background: transparent; border: 1px solid var(--border); color: var(--text-muted); transition: .15s; } .icon-btn:hover { color: var(--text); background: var(--surface-2); } /* page is pushed below the fixed nav */ main { padding-top: var(--nav-h); } /* ---------- buttons ---------- */ .btn { display: inline-flex; align-items: center; gap: .5rem; cursor: pointer; padding: .8rem 1.4rem; border-radius: 12px; font-weight: 650; font-size: .95rem; border: 1px solid transparent; transition: .18s; text-align: center; } .btn-primary { background: var(--primary); color: #fff; box-shadow: 0 8px 20px -8px color-mix(in srgb, var(--primary) 60%, transparent); } .btn-primary:hover { background: color-mix(in srgb, var(--primary) 90%, #000); transform: translateY(-1px); } .btn-ghost { background: var(--surface); color: var(--text); border-color: var(--border); box-shadow: var(--shadow); } .btn-ghost:hover { transform: translateY(-1px); box-shadow: var(--shadow-lg); } .btn svg { width: 1rem; height: 1rem; } /* ---------- hero ---------- */ .hero { position: relative; min-height: calc(100vh - var(--nav-h)); display: flex; align-items: center; justify-content: center; overflow: hidden; text-align: center; } .hero::before { content: ""; position: absolute; inset: 0; z-index: 0; background: radial-gradient(60% 50% at 20% 10%, color-mix(in srgb, var(--primary) 18%, transparent), transparent 70%), radial-gradient(50% 50% at 85% 30%, color-mix(in srgb, var(--secondary) 16%, transparent), transparent 70%); } .hero-inner { position: relative; z-index: 1; max-width: 52rem; padding: 5rem 1.5rem; } .hero h1 { font-size: clamp(2.25rem, 6vw, 4rem); font-weight: 800; margin: 0; } .hero h1 .see { color: var(--primary); } .hero h1 .touch { color: var(--secondary); } .hero p.lead { font-size: clamp(1.05rem, 2.2vw, 1.3rem); color: var(--text-muted); margin: 1.5rem auto 0; max-width: 38rem; } .hero-cta { margin-top: 2.25rem; display: flex; flex-wrap: wrap; gap: 1rem; justify-content: center; } .hero-eyebrow { display: inline-flex; align-items: center; gap: .45rem; font-weight: 600; color: var(--text-muted); font-size: .98rem; margin: 0 0 .75rem; } .hero-demo { margin: 1.75rem auto .25rem; max-width: 46rem; } .hero-demo canvas { width: 100%; display: block; } .hero-slider input[type="range"] { -webkit-appearance: none; appearance: none; width: min(34rem, 92%); height: 8px; border-radius: 6px; background: color-mix(in srgb, #f97316 25%, var(--surface-2)); accent-color: #f97316; outline: none; cursor: pointer; } .hero-slider input[type="range"]::-webkit-slider-thumb { -webkit-appearance: none; appearance: none; width: 26px; height: 26px; border-radius: 50%; background: #f97316; border: 3px solid var(--surface); box-shadow: 0 2px 8px rgba(249,115,22,.5); cursor: grab; } .hero-slider input[type="range"]::-moz-range-thumb { width: 24px; height: 24px; border-radius: 50%; background: #f97316; border: 3px solid var(--surface); cursor: grab; } .hero-slider label { display: block; margin-top: .7rem; color: #f97316; font-weight: 700; font-size: 1.02rem; } /* ---------- sections ---------- */ .section { padding: 5.5rem 0; } .section.alt { background: var(--bg-soft); } .section-head { text-align: center; max-width: 40rem; margin: 0 auto 3.5rem; } .section-head h2 { font-size: clamp(1.75rem, 4vw, 2.4rem); margin: 0 0 .75rem; } .section-head p { color: var(--text-muted); margin: 0; } /* feature cards */ .features { display: grid; grid-template-columns: repeat(auto-fit, minmax(220px, 1fr)); gap: 1.25rem; } .feature { border: 1px solid var(--border); border-radius: var(--radius); padding: 1.5rem; background: var(--surface); box-shadow: var(--shadow); transition: .2s; } .feature:hover { transform: translateY(-4px); box-shadow: var(--shadow-lg); } .feature .emoji { font-size: 2.25rem; display: block; margin-bottom: .75rem; } .feature h3 { margin: 0 0 .4rem; font-size: 1.1rem; } .feature p { margin: 0; color: var(--text-muted); font-size: .92rem; } /* curriculum */ .courses { display: grid; grid-template-columns: repeat(auto-fit, minmax(280px, 1fr)); gap: 1.5rem; align-items: start; } .course-card { border: 1px solid var(--border); border-radius: var(--radius); overflow: hidden; background: var(--surface); box-shadow: var(--shadow); border-left: 4px solid var(--accent, var(--primary)); } .course-card .ch { padding: 1.1rem 1.4rem; border-bottom: 1px solid var(--border); } .course-card .ch h3 { margin: 0; font-size: 1.15rem; } .course-card .ch span { font-size: .85rem; color: var(--text-faint); } .course-card ul { list-style: none; margin: 0; padding: .4rem 0; } .course-card li a { display: flex; align-items: center; gap: .7rem; padding: .55rem 1.4rem; font-size: .92rem; color: var(--text-muted); transition: .12s; } .course-card li a:hover { background: var(--surface-2); color: var(--text); } .sec-num { font-family: var(--mono); font-size: .72rem; color: var(--primary); display: inline-block; min-width: 2.2rem; margin-right: .45rem; } .sec-dot { width: .55rem; height: .55rem; border-radius: 50%; border: 2px solid var(--border); flex-shrink: 0; } li a:hover .sec-dot { border-color: var(--primary); } /* about */ .about { display: flex; flex-wrap: wrap; align-items: center; gap: 3rem; } .about .avatar { width: 11rem; height: 11rem; border-radius: var(--radius); flex-shrink: 0; background: linear-gradient(135deg, color-mix(in srgb, var(--primary) 22%, transparent), color-mix(in srgb, var(--secondary) 22%, transparent)); display: flex; align-items: center; justify-content: center; font-size: 3.5rem; font-weight: 800; color: color-mix(in srgb, var(--primary) 45%, transparent); } .about .bio { flex: 1; min-width: 16rem; } .about .bio p { color: var(--text-muted); } /* ---------- footer ---------- */ .footer { border-top: 1px solid var(--border); padding: 2.5rem 0; color: var(--text-faint); font-size: .9rem; } .footer .container { display: flex; flex-wrap: wrap; gap: 1rem; justify-content: space-between; align-items: center; } /* ============================================================ LESSON LAYOUT ============================================================ */ .lesson-wrap { max-width: var(--maxw); margin: 0 auto; display: flex; gap: 2.5rem; padding: 1.5rem 1.25rem 4rem; } .sidebar { width: 16rem; flex-shrink: 0; } .sidebar-sticky { position: sticky; top: calc(var(--nav-h) + 1rem); max-height: calc(100vh - var(--nav-h) - 2rem); overflow-y: auto; padding-right: .5rem; } .sidebar h4 { font-size: .75rem; text-transform: uppercase; letter-spacing: .08em; color: var(--text-faint); margin: 1.2rem 0 .5rem; } .sidebar a { display: block; padding: .35rem .6rem; border-radius: 8px; font-size: .85rem; color: var(--text-muted); transition: .12s; } .sidebar a:hover { background: var(--surface-2); color: var(--text); } .sidebar a.active { background: color-mix(in srgb, var(--primary) 14%, transparent); color: var(--primary); font-weight: 650; } .sidebar a .n { font-family: var(--mono); font-size: .72rem; color: var(--text-faint); margin-right: .4rem; } .lesson { flex: 1; min-width: 0; max-width: 48rem; } .lesson-eyebrow { font-family: var(--mono); font-size: .8rem; color: var(--primary); } .lesson h1 { font-size: clamp(1.8rem, 4vw, 2.5rem); margin: .25rem 0 1.5rem; } .lesson h2 { font-size: 1.5rem; margin: 2.5rem 0 .75rem; } .lesson h3 { font-size: 1.15rem; margin: 1.75rem 0 .5rem; } .lesson p { color: var(--text-muted); } .lesson .lede { font-size: 1.15rem; color: var(--text); } .lesson ul, .lesson ol { color: var(--text-muted); } .lesson strong { color: var(--text); } .lesson code { font-family: var(--mono); font-size: .88em; background: var(--surface-2); padding: .1rem .35rem; border-radius: 5px; } .callout { border: 1px solid var(--border); border-left: 4px solid var(--secondary); background: var(--surface); border-radius: 12px; padding: 1rem 1.25rem; margin: 1.5rem 0; } .callout.key { border-left-color: var(--primary); } .callout p:last-child { margin-bottom: 0; } .callout p:first-child { margin-top: 0; } /* prev / next nav */ .lesson-nav { display: flex; justify-content: space-between; gap: 1rem; margin-top: 3.5rem; padding-top: 1.75rem; border-top: 1px solid var(--border); } .lesson-nav a { display: flex; align-items: center; gap: .7rem; color: var(--primary); font-weight: 600; max-width: 48%; } .lesson-nav a.next { margin-left: auto; text-align: right; } .lesson-nav .lbl { display: block; font-size: .72rem; color: var(--text-faint); text-transform: uppercase; letter-spacing: .06em; } .lesson-nav svg { width: 1.1rem; height: 1.1rem; flex-shrink: 0; } /* ============================================================ INTERACTIVE VIZ COMPONENTS ============================================================ */ .viz { border: 1px solid var(--border); border-radius: var(--radius); background: var(--surface); box-shadow: var(--shadow); padding: 1.25rem; margin: 1.75rem 0; } .viz-title { font-weight: 700; font-size: 1rem; margin: 0 0 .25rem; } .viz-sub { font-size: .85rem; color: var(--text-faint); margin: 0 0 1rem; } .viz canvas { width: 100%; height: auto; display: block; border-radius: 10px; background: var(--bg-soft); } .controls { display: flex; flex-wrap: wrap; gap: .9rem 1.25rem; align-items: flex-end; margin-bottom: 1rem; } .control { display: flex; flex-direction: column; gap: .3rem; } .control label { font-size: .78rem; color: var(--text-muted); font-weight: 600; } .control .val { font-family: var(--mono); color: var(--primary); } .control input[type="range"] { width: 11rem; accent-color: var(--primary); } .seg { display: inline-flex; border: 1px solid var(--border); border-radius: 10px; overflow: hidden; } .seg button { padding: .4rem .8rem; font-size: .82rem; font-weight: 600; background: var(--surface); color: var(--text-muted); border: none; cursor: pointer; transition: .12s; } .seg button + button { border-left: 1px solid var(--border); } .seg button.active { background: var(--primary); color: #fff; } .stat-row { display: flex; flex-wrap: wrap; gap: 1.5rem; margin-top: 1rem; } .stat { display: flex; flex-direction: column; } .stat .k { font-size: .72rem; text-transform: uppercase; letter-spacing: .05em; color: var(--text-faint); } .stat .v { font-family: var(--mono); font-size: 1.25rem; font-weight: 700; color: var(--text); } .btn-sm { padding: .5rem .9rem; font-size: .85rem; border-radius: 10px; } /* ---------- mobile ---------- */ .menu-toggle { display: none; } @media (max-width: 860px) { .lesson-wrap { flex-direction: column; padding-top: 1rem; } .sidebar { width: 100%; } .sidebar-sticky { position: static; max-height: none; } .nav-links .nav-link.hide-mobile { display: none; } } .animate-up { animation: up .6s ease both; } @keyframes up { from { opacity: 0; transform: translateY(16px); } to { opacity: 1; transform: none; } }