/* ===== CSS Variables & Theme ===== */
:root {
    --bg-primary: #1a1a2e;
    --bg-secondary: #16213e;
    --bg-tertiary: #0f3460;
    --bg-card: #1e2746;
    --bg-input: #1a2340;
    --bg-hover: #2a3a5c;
    --text-primary: #e0e0e0;
    --text-secondary: #a0a8c0;
    --text-muted: #6b7394;
    --accent: #6c63ff;
    --accent-hover: #5a52d5;
    --accent-glow: rgba(108, 99, 255, 0.3);
    --border: #2a3456;
    --border-focus: #6c63ff;
    --success: #4caf50;
    --warning: #ff9800;
    --error: #f44336;
    --shadow: rgba(0, 0, 0, 0.3);
    --scrollbar-bg: #1a1a2e;
    --scrollbar-thumb: #2a3456;
    --radius: 8px;
    --radius-lg: 12px;
    --transition: 0.2s ease;
}

[data-theme="light"] {
    --bg-primary: #f5f5f5;
    --bg-secondary: #ffffff;
    --bg-tertiary: #e8eaf6;
    --bg-card: #ffffff;
    --bg-input: #f0f2f5;
    --bg-hover: #e3e7ef;
    --text-primary: #1a1a2e;
    --text-secondary: #555770;
    --text-muted: #8890a8;
    --border: #d0d5e0;
    --border-focus: #6c63ff;
    --shadow: rgba(0, 0, 0, 0.08);
    --scrollbar-bg: #f5f5f5;
    --scrollbar-thumb: #c0c5d0;
}

/* ===== Reset ===== */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { font-size: 18px; scroll-behavior: smooth; }

body {
    font-family: 'Segoe UI', 'Noto Sans SC', -apple-system, BlinkMacSystemFont, sans-serif;
    background: var(--bg-primary);
    color: var(--text-primary);
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    overflow: hidden;
}

/* ===== Scrollbar ===== */
::-webkit-scrollbar { width: 6px; height: 6px; }
::-webkit-scrollbar-track { background: var(--scrollbar-bg); }
::-webkit-scrollbar-thumb { background: var(--scrollbar-thumb); border-radius: 3px; }
::-webkit-scrollbar-thumb:hover { background: var(--accent); }

/* ===== Shared utilities ===== */
.form-divider { height: 1px; background: var(--border); margin: 16px 0; }

.section-title {
    font-size: 0.75rem; font-weight: 700; color: var(--text-muted);
    text-transform: uppercase; letter-spacing: 1px;
    margin-bottom: 10px; margin-top: 4px;
}

/* ===== Tooltip ===== */
[data-tooltip] { position: relative; }
[data-tooltip]::after {
    content: attr(data-tooltip);
    position: absolute; bottom: calc(100% + 6px); left: 50%;
    transform: translateX(-50%);
    background: var(--bg-tertiary); color: var(--text-primary);
    padding: 4px 8px; border-radius: 4px; font-size: 0.75rem;
    white-space: nowrap; opacity: 0; pointer-events: none;
    transition: opacity var(--transition); z-index: 1000;
    border: 1px solid var(--border);
}
[data-tooltip]:hover::after { opacity: 1; }

/* ===== Animations ===== */
@keyframes pulse { 0%, 100% { opacity: 1; } 50% { opacity: 0.7; } }
@keyframes spin  { to { transform: rotate(360deg); } }