/* ============================================
   ToolPulse Design System
   ============================================ */

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

html {
    scroll-behavior: smooth;
    -webkit-text-size-adjust: 100%;
    text-size-adjust: 100%;
}

body {
    font-family: var(--font-sans);
    font-size: var(--text-base);
    line-height: 1.6;
    color: var(--color-text-primary);
    background-color: var(--color-bg-primary);
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
    overflow-x: hidden;
    min-height: 100vh;
}

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

img, svg {
    display: block;
    max-width: 100%;
}

button, input, textarea, select {
    font: inherit;
    color: inherit;
    border: none;
    outline: none;
    background: none;
}

button {
    cursor: pointer;
}

ul, ol {
    list-style: none;
}

/* --- Design Tokens (Dark Theme — Default) --- */
:root,
[data-theme="dark"] {
    /* Background */
    --color-bg-primary: #07071a;
    --color-bg-secondary: #0d0d2b;
    --color-bg-tertiary: #151540;
    --color-bg-elevated: #1a1a4a;
    --color-bg-card: rgba(255, 255, 255, 0.025);
    --color-bg-card-hover: rgba(255, 255, 255, 0.055);
    --color-bg-input: rgba(255, 255, 255, 0.04);
    --color-bg-input-hover: rgba(255, 255, 255, 0.07);
    --color-bg-input-focus: rgba(255, 255, 255, 0.06);
    --color-bg-code: rgba(255, 255, 255, 0.06);

    /* Borders */
    --color-border: rgba(255, 255, 255, 0.07);
    --color-border-hover: rgba(255, 255, 255, 0.14);
    --color-border-focus: rgba(108, 99, 255, 0.5);
    --color-border-subtle: rgba(255, 255, 255, 0.04);

    /* Text */
    --color-text-primary: #eeeeff;
    --color-text-secondary: #9999cc;
    --color-text-tertiary: #6666aa;
    --color-text-muted: #4d4d88;
    --color-text-inverse: #07071a;

    /* Accent */
    --color-accent-1: #6C63FF;
    --color-accent-2: #3B82F6;
    --color-accent-3: #8B5CF6;
    --color-accent-gradient: linear-gradient(135deg, #6C63FF 0%, #3B82F6 50%, #06B6D4 100%);
    --color-accent-gradient-hover: linear-gradient(135deg, #7C73FF 0%, #4B92FF 50%, #16C6E4 100%);
    --color-accent-glow: rgba(108, 99, 255, 0.2);
    --color-accent-glow-strong: rgba(108, 99, 255, 0.35);

    /* Semantic */
    --color-success: #10B981;
    --color-success-bg: rgba(16, 185, 129, 0.1);
    --color-success-border: rgba(16, 185, 129, 0.25);
    --color-warning: #F59E0B;
    --color-warning-bg: rgba(245, 158, 11, 0.1);
    --color-warning-border: rgba(245, 158, 11, 0.25);
    --color-error: #EF4444;
    --color-error-bg: rgba(239, 68, 68, 0.1);
    --color-error-border: rgba(239, 68, 68, 0.25);
    --color-info: #3B82F6;
    --color-info-bg: rgba(59, 130, 246, 0.1);
    --color-info-border: rgba(59, 130, 246, 0.25);

    /* Category colors */
    --color-cat-image: #F472B6;
    --color-cat-image-bg: rgba(244, 114, 182, 0.1);
    --color-cat-text: #34D399;
    --color-cat-text-bg: rgba(52, 211, 153, 0.1);
    --color-cat-developer: #60A5FA;
    --color-cat-developer-bg: rgba(96, 165, 250, 0.1);
    --color-cat-converter: #FBBF24;
    --color-cat-converter-bg: rgba(251, 191, 36, 0.1);

    /* Shadows */
    --shadow-xs: 0 1px 3px rgba(0, 0, 0, 0.4);
    --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.5);
    --shadow-md: 0 4px 20px rgba(0, 0, 0, 0.5);
    --shadow-lg: 0 8px 40px rgba(0, 0, 0, 0.6);
    --shadow-xl: 0 16px 60px rgba(0, 0, 0, 0.7);
    --shadow-glow: 0 0 25px var(--color-accent-glow);
    --shadow-glow-strong: 0 0 40px var(--color-accent-glow-strong);
    --shadow-card: 0 4px 24px rgba(0, 0, 0, 0.3), inset 0 1px 0 rgba(255,255,255,0.03);
    --shadow-card-hover: 0 8px 40px rgba(0, 0, 0, 0.4), inset 0 1px 0 rgba(255,255,255,0.06);

    /* Glass */
    --glass-bg: rgba(15, 15, 40, 0.7);
    --glass-border: rgba(255, 255, 255, 0.08);
    --glass-blur: 20px;

    /* Scrollbar */
    --scrollbar-bg: transparent;
    --scrollbar-thumb: rgba(255, 255, 255, 0.12);
    --scrollbar-thumb-hover: rgba(255, 255, 255, 0.2);
}

/* --- Light Theme --- */
[data-theme="light"] {
    --color-bg-primary: #f5f5ff;
    --color-bg-secondary: #ffffff;
    --color-bg-tertiary: #eef0ff;
    --color-bg-elevated: #ffffff;
    --color-bg-card: rgba(0, 0, 0, 0.02);
    --color-bg-card-hover: rgba(0, 0, 0, 0.04);
    --color-bg-input: rgba(0, 0, 0, 0.03);
    --color-bg-input-hover: rgba(0, 0, 0, 0.05);
    --color-bg-input-focus: rgba(0, 0, 0, 0.04);
    --color-bg-code: rgba(0, 0, 0, 0.04);

    --color-border: rgba(0, 0, 0, 0.08);
    --color-border-hover: rgba(0, 0, 0, 0.15);
    --color-border-subtle: rgba(0, 0, 0, 0.04);

    --color-text-primary: #1a1a2e;
    --color-text-secondary: #555577;
    --color-text-tertiary: #8888aa;
    --color-text-muted: #aaaacc;
    --color-text-inverse: #eeeeff;

    --color-accent-glow: rgba(108, 99, 255, 0.08);
    --color-accent-glow-strong: rgba(108, 99, 255, 0.15);

    --color-cat-image-bg: rgba(244, 114, 182, 0.08);
    --color-cat-text-bg: rgba(52, 211, 153, 0.08);
    --color-cat-developer-bg: rgba(96, 165, 250, 0.08);
    --color-cat-converter-bg: rgba(251, 191, 36, 0.08);

    --shadow-xs: 0 1px 3px rgba(0, 0, 0, 0.06);
    --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.06);
    --shadow-md: 0 4px 20px rgba(0, 0, 0, 0.08);
    --shadow-lg: 0 8px 40px rgba(0, 0, 0, 0.1);
    --shadow-xl: 0 16px 60px rgba(0, 0, 0, 0.12);
    --shadow-card: 0 2px 12px rgba(0, 0, 0, 0.06), inset 0 1px 0 rgba(255,255,255,0.8);
    --shadow-card-hover: 0 6px 30px rgba(0, 0, 0, 0.1), inset 0 1px 0 rgba(255,255,255,0.9);

    --glass-bg: rgba(255, 255, 255, 0.75);
    --glass-border: rgba(0, 0, 0, 0.06);

    --scrollbar-thumb: rgba(0, 0, 0, 0.12);
    --scrollbar-thumb-hover: rgba(0, 0, 0, 0.2);
}

/* --- Spacing Scale --- */
:root {
    --space-1: 4px;
    --space-2: 8px;
    --space-3: 12px;
    --space-4: 16px;
    --space-5: 20px;
    --space-6: 24px;
    --space-8: 32px;
    --space-10: 40px;
    --space-12: 48px;
    --space-16: 64px;
    --space-20: 80px;
    --space-24: 96px;

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

    --text-xs: 0.7rem;
    --text-sm: 0.82rem;
    --text-base: 0.95rem;
    --text-lg: 1.08rem;
    --text-xl: 1.22rem;
    --text-2xl: 1.45rem;
    --text-3xl: 1.85rem;
    --text-4xl: 2.4rem;
    --text-5xl: 3.2rem;

    --leading-tight: 1.2;
    --leading-normal: 1.6;
    --leading-relaxed: 1.8;

    --tracking-tight: -0.02em;
    --tracking-normal: 0;
    --tracking-wide: 0.02em;

    /* Radius */
    --radius-xs: 4px;
    --radius-sm: 6px;
    --radius-md: 10px;
    --radius-lg: 14px;
    --radius-xl: 20px;
    --radius-2xl: 28px;
    --radius-full: 9999px;

    /* Transition */
    --ease-out: cubic-bezier(0.16, 1, 0.3, 1);
    --ease-in-out: cubic-bezier(0.4, 0, 0.2, 1);
    --ease-spring: cubic-bezier(0.34, 1.56, 0.64, 1);

    --duration-fast: 120ms;
    --duration-normal: 220ms;
    --duration-slow: 350ms;
    --duration-slower: 500ms;

    --transition-colors: color var(--duration-normal) var(--ease-in-out),
                         background-color var(--duration-normal) var(--ease-in-out),
                         border-color var(--duration-normal) var(--ease-in-out);
    --transition-transform: transform var(--duration-normal) var(--ease-out);
    --transition-shadow: box-shadow var(--duration-normal) var(--ease-in-out);
    --transition-all: all var(--duration-normal) var(--ease-in-out);

    /* Z-index */
    --z-base: 1;
    --z-dropdown: 50;
    --z-sticky: 80;
    --z-nav: 100;
    --z-overlay: 150;
    --z-modal: 200;
    --z-toast: 300;

    /* Container */
    --container-max: 1280px;
    --container-padding: var(--space-6);
}

/* --- Typography Base --- */
h1, h2, h3, h4, h5, h6 {
    font-weight: 700;
    line-height: var(--leading-tight);
    letter-spacing: var(--tracking-tight);
    color: var(--color-text-primary);
}

h1 { font-size: var(--text-4xl); }
h2 { font-size: var(--text-3xl); }
h3 { font-size: var(--text-2xl); }
h4 { font-size: var(--text-xl); }
h5 { font-size: var(--text-lg); }

p {
    color: var(--color-text-secondary);
    line-height: var(--leading-normal);
}

code, pre {
    font-family: var(--font-mono);
}

::selection {
    background: var(--color-accent-1);
    color: white;
}

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

::-webkit-scrollbar-track {
    background: var(--scrollbar-bg);
}

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

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

/* Firefox */
* {
    scrollbar-width: thin;
    scrollbar-color: var(--scrollbar-thumb) var(--scrollbar-bg);
}

/* --- Gradient Text Utility --- */
.gradient-text {
    background: var(--color-accent-gradient);
    -webkit-background-clip: text;
    background-clip: text;
    -webkit-text-fill-color: transparent;
}

/* --- Screen Reader Only --- */
.sr-only {
    position: absolute;
    width: 1px;
    height: 1px;
    padding: 0;
    margin: -1px;
    overflow: hidden;
    clip: rect(0, 0, 0, 0);
    white-space: nowrap;
    border-width: 0;
}