/* ========================================
   4EverFile — Design System
   Premium dark-mode blockchain aesthetic
   ======================================== */

/* ---- Google Fonts ---- */
@import url('https://fonts.googleapis.com/css2?family=Inter:wght@300;400;500;600;700;800;900&family=JetBrains+Mono:wght@400;500;600&display=swap');

/* ---- CSS Custom Properties ---- */
:root {
    /* Surfaces */
    --fs-bg-primary: #060a13;
    --fs-bg-secondary: #0d1420;
    --fs-bg-elevated: #131d2e;
    --fs-bg-card: #162033;
    --fs-bg-hover: #1c2a42;
    --fs-bg-input: #0f1926;

    /* Accent Colors */
    --fs-accent: #3b82f6;
    --fs-accent-hover: #60a5fa;
    --fs-accent-glow: rgba(59, 130, 246, 0.25);
    --fs-accent-subtle: rgba(59, 130, 246, 0.08);

    /* Status Colors */
    --fs-success: #10b981;
    --fs-success-glow: rgba(16, 185, 129, 0.2);
    --fs-warning: #f59e0b;
    --fs-warning-glow: rgba(245, 158, 11, 0.2);
    --fs-error: #ef4444;
    --fs-error-glow: rgba(239, 68, 68, 0.2);
    --fs-info: #06b6d4;

    /* Text */
    --fs-text-primary: #f1f5f9;
    --fs-text-secondary: #94a3b8;
    --fs-text-muted: #64748b;
    --fs-text-accent: #93c5fd;

    /* Borders */
    --fs-border: rgba(59, 130, 246, 0.12);
    --fs-border-strong: rgba(59, 130, 246, 0.25);
    --fs-border-subtle: rgba(255, 255, 255, 0.06);

    /* Glass */
    --fs-glass: rgba(13, 20, 32, 0.85);
    --fs-glass-border: rgba(59, 130, 246, 0.15);

    /* Gradients */
    --fs-gradient-primary: linear-gradient(135deg, #3b82f6 0%, #8b5cf6 100%);
    --fs-gradient-surface: linear-gradient(180deg, #0d1420 0%, #060a13 100%);
    --fs-gradient-card: linear-gradient(135deg, #162033 0%, #131d2e 100%);
    --fs-gradient-success: linear-gradient(135deg, #10b981 0%, #059669 100%);

    /* Shadows */
    --fs-shadow-sm: 0 1px 3px rgba(0, 0, 0, 0.3);
    --fs-shadow-md: 0 4px 12px rgba(0, 0, 0, 0.4);
    --fs-shadow-lg: 0 8px 32px rgba(0, 0, 0, 0.5);
    --fs-shadow-glow: 0 0 20px var(--fs-accent-glow);

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

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

    /* Radius */
    --fs-radius-sm: 6px;
    --fs-radius-md: 10px;
    --fs-radius-lg: 16px;
    --fs-radius-xl: 24px;
    --fs-radius-full: 9999px;

    /* Transitions */
    --fs-transition-fast: 150ms ease;
    --fs-transition-base: 250ms ease;
    --fs-transition-slow: 400ms ease;
}

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

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

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

a {
    color: var(--fs-accent);
    text-decoration: none;
    transition: color var(--fs-transition-fast);
}
a:hover { color: var(--fs-accent-hover); }

/* ---- Typography ---- */
h1, h2, h3, h4, h5, h6 {
    font-weight: 700;
    line-height: 1.2;
    color: var(--fs-text-primary);
}
h1 { font-size: 2.5rem; letter-spacing: -0.02em; }
h2 { font-size: 1.875rem; letter-spacing: -0.015em; }
h3 { font-size: 1.5rem; }
h4 { font-size: 1.25rem; }

.text-mono { font-family: var(--fs-font-mono); }
.text-secondary { color: var(--fs-text-secondary); }
.text-muted { color: var(--fs-text-muted); }
.text-accent { color: var(--fs-text-accent); }
.text-success { color: var(--fs-success); }
.text-warning { color: var(--fs-warning); }
.text-error { color: var(--fs-error); }

/* ---- Layout ---- */
.container {
    max-width: 1280px;
    margin: 0 auto;
    padding: 0 var(--fs-spacing-lg);
}

.flex { display: flex; }
.flex-col { flex-direction: column; }
.items-center { align-items: center; }
.justify-between { justify-content: space-between; }
.gap-sm { gap: var(--fs-spacing-sm); }
.gap-md { gap: var(--fs-spacing-md); }
.gap-lg { gap: var(--fs-spacing-lg); }

/* ---- App Layout ---- */
.app-layout {
    display: grid;
    grid-template-columns: 260px 1fr;
    min-height: 100vh;
}

.sidebar {
    background: var(--fs-bg-secondary);
    border-right: 1px solid var(--fs-border);
    padding: var(--fs-spacing-lg);
    position: sticky;
    top: 0;
    height: 100vh;
    overflow-y: auto;
    display: flex;
    flex-direction: column;
}

.main-content {
    padding: var(--fs-spacing-xl);
    overflow-y: auto;
}

/* ---- Sidebar ---- */
.sidebar-logo {
    display: flex;
    align-items: center;
    gap: var(--fs-spacing-sm);
    padding-bottom: var(--fs-spacing-xl);
    border-bottom: 1px solid var(--fs-border);
    margin-bottom: var(--fs-spacing-lg);
}

.sidebar-logo .logo-icon {
    width: 36px;
    height: 36px;
    background: var(--fs-gradient-primary);
    border-radius: var(--fs-radius-md);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.25rem;
    box-shadow: var(--fs-shadow-glow);
}

.sidebar-logo .logo-text {
    font-size: 1.25rem;
    font-weight: 800;
    letter-spacing: -0.02em;
    background: var(--fs-gradient-primary);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.sidebar-nav {
    flex: 1;
    display: flex;
    flex-direction: column;
    gap: var(--fs-spacing-xs);
}

.nav-item {
    display: flex;
    align-items: center;
    gap: var(--fs-spacing-sm);
    padding: 10px 14px;
    border-radius: var(--fs-radius-md);
    color: var(--fs-text-secondary);
    font-size: 0.9rem;
    font-weight: 500;
    transition: all var(--fs-transition-fast);
    cursor: pointer;
}
.nav-item:hover {
    background: var(--fs-bg-hover);
    color: var(--fs-text-primary);
}
.nav-item.active {
    background: var(--fs-accent-subtle);
    color: var(--fs-accent);
    border: 1px solid var(--fs-border);
}

/* ---- Scrollbar ---- */
::-webkit-scrollbar { width: 6px; }
::-webkit-scrollbar-track { background: transparent; }
::-webkit-scrollbar-thumb {
    background: var(--fs-border-strong);
    border-radius: 3px;
}
::-webkit-scrollbar-thumb:hover { background: var(--fs-text-muted); }

/* ---- Utility Classes ---- */
.sidebar-bottom {
    margin-top: auto;
    padding-top: var(--fs-spacing-lg);
    border-top: 1px solid var(--fs-border);
}

.text-center { text-align: center; }
.mt-sm { margin-top: var(--fs-spacing-sm); }
.mt-md { margin-top: var(--fs-spacing-md); }
.mt-lg { margin-top: var(--fs-spacing-lg); }
.mb-sm { margin-bottom: var(--fs-spacing-sm); }
.mb-md { margin-bottom: var(--fs-spacing-md); }
.pt-md { padding-top: var(--fs-spacing-md); }
.font-mono { font-family: var(--fs-font-mono); font-size: 0.85rem; }
.cursor-pointer { cursor: pointer; }
.hidden { display: none; }

.divider-text {
    text-align: center;
    color: var(--fs-text-muted);
    margin: 24px 0;
    font-size: 0.8rem;
    text-transform: uppercase;
    letter-spacing: 0.1em;
}

.verify-drop-text { font-size: 1.1rem; color: var(--fs-text-secondary); }
.verify-drop-hint { font-size: 0.8rem; color: var(--fs-text-muted); margin-top: 8px; }
.hash-input-row { display: flex; gap: 8px; }

.upload-file-input { display: none; }

.result-subtitle {
    color: var(--fs-text-secondary);
    margin-top: 4px;
}

.result-muted-note {
    color: var(--fs-text-muted);
    text-align: center;
    margin-top: 16px;
}