/* CSS Variables for theming */
:root {
    /* Light theme (Apple-like) */
    --primary-color: #007AFF;
    --primary-dark: #0056CC;
    --secondary-color: #5856D6;
    --accent-color: #FF2D55;

    --background-color: #FFFFFF;
    --surface-color: #F2F2F7;
    --surface-color-dark: #E5E5EA;

    --text-primary: #000000;
    --text-secondary: #3C3C43;
    --text-tertiary: #8E8E93;

    --border-color: #C7C7CC;
    --border-color-light: #E5E5EA;

    --shadow-color: rgba(0, 0, 0, 0.1);
    --shadow-color-light: rgba(0, 0, 0, 0.05);

    --card-background: #FFFFFF;
    --card-shadow: 0 4px 20px var(--shadow-color-light);

    --gradient-primary: linear-gradient(135deg, #007AFF 0%, #5856D6 100%);
    --gradient-accent: linear-gradient(135deg, #FF2D55 0%, #FF9500 100%);

    --transition-fast: 0.2s ease;
    --transition-medium: 0.3s ease;
    --transition-slow: 0.5s ease;

    --border-radius: 12px;
    --border-radius-sm: 8px;
    --border-radius-lg: 20px;

    --font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
}

[data-theme="dark"] {
    /* Dark theme (Apple-like) */
    --primary-color: #0A84FF;
    --primary-dark: #409CFF;
    --secondary-color: #5E5CE6;
    --accent-color: #FF375F;

    --background-color: #000000;
    --surface-color: #1C1C1E;
    --surface-color-dark: #2C2C2E;

    --text-primary: #FFFFFF;
    --text-secondary: #EBEBF5;
    --text-tertiary: #8E8E93;

    --border-color: #38383A;
    --border-color-light: #2C2C2E;

    --shadow-color: rgba(0, 0, 0, 0.3);
    --shadow-color-light: rgba(0, 0, 0, 0.2);

    --card-background: #1C1C1E;
    --card-shadow: 0 4px 20px var(--shadow-color-light);

    --gradient-primary: linear-gradient(135deg, #0A84FF 0%, #5E5CE6 100%);
    --gradient-accent: linear-gradient(135deg, #FF375F 0%, #FF9F0A 100%);
}

/* Reset and base styles */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

html {
    scroll-behavior: smooth;
}

body {
    font-family: var(--font-family);
    background-color: var(--background-color);
    color: var(--text-primary);
    line-height: 1.6;
    transition: background-color var(--transition-medium), color var(--transition-medium);
    overflow-x: hidden;
}

.container {
    width: 100%;
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 24px;
}

/* Typography */
h1, h2, h3, h4 {
    font-weight: 700;
    line-height: 1.2;
}

h1 {
    font-size: 3.5rem;
}

h2 {
    font-size: 2.5rem;
}

h3 {
    font-size: 1.5rem;
}

p {
    font-size: 1rem;
    color: var(--text-secondary);
}

.highlight {
    color: var(--primary-color);
    font-weight: 600;
}

.section-title {
    text-align: center;
    margin-bottom: 3rem;
    position: relative;
}

.section-title::after {
    content: '';
    position: absolute;
    bottom: -10px;
    left: 50%;
    transform: translateX(-50%);
    width: 60px;
    height: 4px;
    background: var(--gradient-primary);
    border-radius: 2px;
}

/* Buttons */
.btn {
    display: inline-block;
    padding: 12px 28px;
    border-radius: var(--border-radius);
    font-weight: 600;
    text-decoration: none;
    transition: all var(--transition-fast);
    border: none;
    cursor: pointer;
    font-size: 1rem;
}

.btn-primary {
    background: var(--gradient-primary);
    color: white;
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 20px rgba(0, 122, 255, 0.3);
}

.btn-secondary {
    background: transparent;
    color: var(--primary-color);
    border: 2px solid var(--primary-color);
}

.btn-secondary:hover {
    background: var(--primary-color);
    color: white;
    transform: translateY(-2px);
}

/* Utility classes */
.text-center {
    text-align: center;
}

.mt-1 { margin-top: 1rem; }
.mt-2 { margin-top: 2rem; }
.mt-3 { margin-top: 3rem; }
.mb-1 { margin-bottom: 1rem; }
.mb-2 { margin-bottom: 2rem; }
.mb-3 { margin-bottom: 3rem; }