/* =============================================================================
   SleepGuardian — Design System & Global Styles
   Theme: "Deep Night" — dark-only, indigo-violet primary
   ============================================================================= */

/* Google Fonts */
@import url('https://fonts.googleapis.com/css2?family=Inter:wght@300;400;500;600;700&family=JetBrains+Mono:wght@300;400;500&display=swap');

/* ── Design Tokens ─────────────────────────────────────────────────────────── */
:root {
    /* Backgrounds */
    --bg-page: #0A0E1A;
    --bg-surface: #121829;
    --bg-surface-raised: #1A2038;
    --bg-surface-hover: #222845;
    --bg-glass: rgba(18, 24, 41, 0.7);
    --bg-glass-strong: rgba(26, 32, 56, 0.85);

    /* Primary — Indigo-Violet */
    --primary: #7C4DFF;
    --primary-light: #B388FF;
    --primary-dark: #5E35B1;
    --primary-glow: rgba(124, 77, 255, 0.25);
    --primary-gradient: linear-gradient(135deg, #7C4DFF, #B388FF);

    /* Secondary — Cool Teal */
    --secondary: #00E5FF;
    --secondary-dim: rgba(0, 229, 255, 0.15);

    /* Status Colors */
    --good: #00E676;
    --good-bg: rgba(0, 230, 118, 0.12);
    --fair: #FFAB00;
    --fair-bg: rgba(255, 171, 0, 0.12);
    --poor: #FF5252;
    --poor-bg: rgba(255, 82, 82, 0.12);
    --snore: #FF6E40;
    --snore-bg: rgba(255, 110, 64, 0.12);

    /* Text */
    --text-primary: #E8EAF6;
    --text-secondary: #9FA8DA;
    --text-muted: #5C6BC0;
    --text-dim: rgba(232, 234, 246, 0.4);

    /* Borders */
    --border-subtle: rgba(255, 255, 255, 0.06);
    --border-medium: rgba(255, 255, 255, 0.1);
    --border-focus: rgba(124, 77, 255, 0.5);

    /* Radius */
    --radius-sm: 8px;
    --radius-md: 12px;
    --radius-lg: 16px;
    --radius-xl: 24px;
    --radius-full: 9999px;

    /* Shadows */
    --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.3);
    --shadow-md: 0 4px 16px rgba(0, 0, 0, 0.4);
    --shadow-lg: 0 8px 32px rgba(0, 0, 0, 0.5);
    --shadow-glow: 0 0 20px rgba(124, 77, 255, 0.2);

    /* Transitions */
    --transition-fast: 150ms ease;
    --transition-normal: 250ms ease;
    --transition-slow: 400ms ease;

    /* Typography */
    --font-sans: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
    --font-mono: 'JetBrains Mono', 'Fira Code', 'Consolas', monospace;

    /* Spacing scale */
    --space-xs: 4px;
    --space-sm: 8px;
    --space-md: 16px;
    --space-lg: 24px;
    --space-xl: 32px;
    --space-2xl: 48px;

    /* Layout */
    --nav-height: 64px;
    --content-max: 1200px;
}

/* ── Reset & Base ──────────────────────────────────────────────────────────── */
*, *::before, *::after {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

html {
    font-size: 16px;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
    scroll-behavior: smooth;
}

body {
    font-family: var(--font-sans);
    background-color: var(--bg-page);
    color: var(--text-primary);
    line-height: 1.6;
    min-height: 100vh;
    overflow-x: hidden;
}

/* ── Custom Scrollbar ──────────────────────────────────────────────────────── */
::-webkit-scrollbar {
    width: 6px;
    height: 6px;
}

::-webkit-scrollbar-track {
    background: transparent;
}

::-webkit-scrollbar-thumb {
    background: var(--text-muted);
    border-radius: var(--radius-full);
}

::-webkit-scrollbar-thumb:hover {
    background: var(--primary);
}

/* Firefox */
* {
    scrollbar-width: thin;
    scrollbar-color: var(--text-muted) transparent;
}

/* ── Typography ────────────────────────────────────────────────────────────── */
h1, h2, h3, h4, h5, h6 {
    font-weight: 600;
    line-height: 1.3;
    color: var(--text-primary);
}

h1 { font-size: 2rem; }
h2 { font-size: 1.5rem; }
h3 { font-size: 1.25rem; }
h4 { font-size: 1.1rem; }

p { color: var(--text-secondary); }

a {
    color: var(--secondary);
    text-decoration: none;
    transition: color var(--transition-fast);
}
a:hover { color: var(--primary-light); }

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

.text-muted { color: var(--text-muted); }
.text-secondary { color: var(--text-secondary); }
.text-good { color: var(--good); }
.text-fair { color: var(--fair); }
.text-poor { color: var(--poor); }
.text-snore { color: var(--snore); }
.text-primary-c { color: var(--primary-light); }

/* ── Utility Classes ───────────────────────────────────────────────────────── */
.hidden { display: none !important; }

.sr-only {
    position: absolute;
    width: 1px;
    height: 1px;
    padding: 0;
    margin: -1px;
    overflow: hidden;
    clip: rect(0,0,0,0);
    border: 0;
}

.fade-in {
    animation: fadeIn var(--transition-slow) forwards;
}

.fade-out {
    animation: fadeOut var(--transition-normal) forwards;
}

.slide-up {
    animation: slideUp var(--transition-slow) forwards;
}

@keyframes fadeIn {
    from { opacity: 0; }
    to   { opacity: 1; }
}

@keyframes fadeOut {
    from { opacity: 1; }
    to   { opacity: 0; }
}

@keyframes slideUp {
    from { opacity: 0; transform: translateY(20px); }
    to   { opacity: 1; transform: translateY(0); }
}

@keyframes pulse {
    0%, 100% { opacity: 1; }
    50%      { opacity: 0.5; }
}

@keyframes shimmer {
    0%   { background-position: -200% 0; }
    100% { background-position: 200% 0; }
}

@keyframes glow-pulse {
    0%, 100% { box-shadow: 0 0 8px var(--primary-glow); }
    50%      { box-shadow: 0 0 20px var(--primary-glow), 0 0 40px rgba(124,77,255,0.1); }
}

/* ── Loading Skeleton ──────────────────────────────────────────────────────── */
.skeleton {
    background: linear-gradient(90deg, var(--bg-surface) 25%, var(--bg-surface-raised) 50%, var(--bg-surface) 75%);
    background-size: 400% 100%;
    animation: shimmer 1.5s ease infinite;
    border-radius: var(--radius-md);
}

.skeleton-text {
    height: 14px;
    margin-bottom: 8px;
    border-radius: var(--radius-sm);
}

.skeleton-text.lg { height: 28px; width: 60%; }
.skeleton-text.md { height: 18px; width: 80%; }
.skeleton-text.sm { height: 14px; width: 40%; }

.skeleton-circle {
    border-radius: 50%;
}

/* ── View Sections ─────────────────────────────────────────────────────────── */
.view-section {
    display: none;
    opacity: 0;
}

.view-section.active {
    display: block;
    animation: fadeIn var(--transition-slow) forwards;
}

/* ── Responsive Container ──────────────────────────────────────────────────── */
.container {
    width: 100%;
    max-width: var(--content-max);
    margin: 0 auto;
    padding: 0 var(--space-md);
}

/* ── Toast Notifications ───────────────────────────────────────────────────── */
.toast-container {
    position: fixed;
    top: 80px;
    right: 20px;
    z-index: 10000;
    display: flex;
    flex-direction: column;
    gap: 8px;
}

.toast {
    padding: 12px 20px;
    border-radius: var(--radius-md);
    background: var(--bg-surface-raised);
    border: 1px solid var(--border-medium);
    color: var(--text-primary);
    font-size: 0.875rem;
    box-shadow: var(--shadow-md);
    animation: slideInRight var(--transition-normal);
    max-width: 360px;
}

.toast.success { border-left: 3px solid var(--good); }
.toast.error   { border-left: 3px solid var(--poor); }
.toast.info    { border-left: 3px solid var(--secondary); }

@keyframes slideInRight {
    from { opacity: 0; transform: translateX(40px); }
    to   { opacity: 1; transform: translateX(0); }
}

/* ── Media Queries ─────────────────────────────────────────────────────────── */
@media (max-width: 768px) {
    :root {
        --nav-height: 56px;
    }
    h1 { font-size: 1.5rem; }
    h2 { font-size: 1.25rem; }
}