:root {
    --mist-100: #F4F7F9;
    --mist-200: #E9EFF3;
    --ink-900: #1B2733;
    --ink-700: #243445;
    --ink-500: #3A4753;
    --ink-400: #5A6673;
    --ink-300: #7C8894;
    --steel-500: #2E7DA6;
    --steel-600: #256A8D;
    --amber-500: #D98E32;
    --steel-soft: rgba(46, 125, 166, 0.10);
    --amber-soft: rgba(217, 142, 50, 0.10);
    --font-head: 'Montserrat', -apple-system, BlinkMacSystemFont, sans-serif;
    --font-body: 'Rubik', -apple-system, BlinkMacSystemFont, sans-serif;
    --font-mono: 'JetBrains Mono', monospace;
}

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

html {
    scroll-behavior: smooth;
    background-color: var(--mist-100);
    color: var(--ink-900);
    font-family: var(--font-body);
}

body {
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    overflow-x: hidden;
    background-color: var(--mist-100);
    color: var(--ink-900);
}

h1, h2, h3, h4, h5, h6 { font-family: var(--font-head); letter-spacing: -0.01em; }

a { text-decoration: none; }

.font-mono-num { font-family: var(--font-mono); }

/* ===== шапка ===== */
.so-header { font-family: var(--font-head); }

.so-header .so-nav { position: relative; letter-spacing: 0.06em; }

.so-header .so-nav::after {
    content: '';
    position: absolute;
    bottom: -5px;
    left: 50%;
    transform: translateX(-50%);
    width: 0;
    height: 2px;
    background: var(--steel-500);
    transition: width 0.2s ease;
}

.so-header .so-nav:hover::after { width: 100%; }

.so-header .so-burger:active { transform: scale(0.94); }

/* ===== hero ===== */
.so-mark {
    background: linear-gradient(100deg, var(--steel-500) 0%, var(--steel-600) 50%, var(--amber-500) 100%);
    -webkit-background-clip: text;
    background-clip: text;
    -webkit-text-fill-color: transparent;
}

.so-panel {
    background: #FFFFFF;
    border: 1px solid rgba(27, 39, 51, 0.12);
    box-shadow: 0 22px 56px rgba(27, 39, 51, 0.10);
}

.so-field {
    background: var(--mist-100);
    border: 1px solid rgba(27, 39, 51, 0.15);
    transition: border-color 0.2s ease, box-shadow 0.2s ease;
}

.so-field:focus-within {
    border-color: var(--steel-500);
    box-shadow: 0 0 0 3px var(--steel-soft);
}

.so-submit {
    background: linear-gradient(100deg, var(--steel-500), var(--steel-600));
    color: #fff;
    transition: filter 0.2s ease, transform 0.15s ease;
}

.so-submit:hover { filter: brightness(1.08); }
.so-submit:active { transform: scale(0.99); }

/* ===== карточки ===== */
.so-card {
    background: #FFFFFF;
    border: 1px solid rgba(27, 39, 51, 0.10);
    box-shadow: 0 8px 26px rgba(27, 39, 51, 0.06);
    transition: transform 0.2s ease, box-shadow 0.2s ease, border-color 0.2s ease;
}

.so-card:hover {
    transform: translateY(-3px);
    box-shadow: 0 18px 42px rgba(27, 39, 51, 0.12);
    border-color: rgba(46, 125, 166, 0.4);
}

.so-stat {
    background: #FFFFFF;
    border: 1px solid rgba(27, 39, 51, 0.10);
}

/* ===== заметки ===== */
.so-note {
    background: var(--mist-200);
    border: 1px solid rgba(27, 39, 51, 0.10);
    border-left: 3px solid var(--steel-500);
}

/* ===== details ===== */
details summary::-webkit-details-marker { display: none; }
details summary { list-style: none; }
details[open] summary { color: var(--steel-500); }