:root {
    --blue-950: #060e1e;
    --blue-900: #0a1628;
    --blue-800: #0f2a52;
    --blue-600: #1d4ed8;
    --blue-400: #60a5fa;
    --cyan-400: #22d3ee;
    --amber-400: #f59e0b;
    --white: #ffffff;
    --slate-100: #f1f5f9;
    --slate-300: #cbd5e1;
    --slate-400: #94a3b8;
    --slate-600: #475569;
    --radius: 12px;
    --shadow-lg: 0 24px 60px rgba(2, 6, 23, 0.35);
    --font-display: 'Plus Jakarta Sans', sans-serif;
    --font-body: 'Inter', sans-serif;
    color-scheme: dark;
    --app-bg: var(--blue-950);
    --text-main: #f8fafc;
    --text-muted: rgba(148, 163, 184, 0.95);
    --surface-1: rgba(15, 23, 42, 0.72);
    --surface-2: rgba(15, 23, 42, 0.95);
    --surface-3: rgba(255, 255, 255, 0.04);
    --border-soft: rgba(148, 163, 184, 0.15);
    --border-strong: rgba(148, 163, 184, 0.22);
    --shell-shadow: 0 24px 60px rgba(2, 6, 23, 0.28);
    --panel-shadow: 0 28px 60px rgba(15, 23, 42, 0.18);
}

body.light {
    color-scheme: light;
    --app-bg: #eef4fb;
    --text-main: #0f172a;
    --text-muted: #64748b;
    --surface-1: rgba(255, 255, 255, 0.88);
    --surface-2: #ffffff;
    --surface-3: rgba(37, 99, 235, 0.06);
    --border-soft: rgba(15, 23, 42, 0.1);
    --border-strong: rgba(37, 99, 235, 0.18);
    --shell-shadow: 0 20px 45px rgba(15, 23, 42, 0.08);
    --panel-shadow: 0 22px 44px rgba(15, 23, 42, 0.08);
}

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

html {
    scroll-behavior: smooth;
}

body {
    font-family: var(--font-body);
    color: var(--text-main);
    background: var(--app-bg);
    overflow-x: hidden;
}

a {
    color: inherit;
    text-decoration: none;
}

button,
input {
    font: inherit;
}

.btn {
    border: 0;
    cursor: pointer;
    border-radius: 10px;
    padding: 0.7rem 1.4rem;
    font-size: 0.9rem;
    font-weight: 600;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    transition: 0.2s ease;
}

.btn-primary {
    color: var(--white);
    background: linear-gradient(135deg, var(--blue-600), #2563eb);
    box-shadow: 0 8px 24px rgba(37, 99, 235, 0.35);
}

.btn-primary:hover {
    transform: translateY(-1px);
}

.btn-ghost {
    color: var(--slate-100);
    border: 1px solid rgba(148, 163, 184, 0.35);
    background: rgba(15, 23, 42, 0.3);
}

.btn-ghost:hover {
    border-color: var(--blue-400);
}

.btn-accent {
    color: #03232f;
    background: linear-gradient(135deg, #06b6d4, var(--cyan-400));
    box-shadow: 0 8px 24px rgba(6, 182, 212, 0.3);
}

.btn-outline {
    color: var(--white);
    border: 1px solid rgba(255, 255, 255, 0.35);
    background: transparent;
}

.btn.full {
    width: 100%;
}