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

:root {
    --color-bg: #fafafa;
    --color-surface: #ffffff;
    --color-text: #1a1a1a;
    --color-text-secondary: #6b7280;
    --color-primary: #ef4444;
    --color-primary-hover: #dc2626;
    --color-border: #e5e7eb;
    --color-error: #dc2626;
    --color-error-bg: #fef2f2;
    --radius: 8px;
    --font-sans: "Inter", -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
    --font-mono: "JetBrains Mono", "Fira Code", monospace;
}

html {
    font-family: var(--font-sans);
    font-size: 16px;
    line-height: 1.6;
    color: var(--color-text);
    background-color: var(--color-bg);
    -webkit-font-smoothing: antialiased;
}

body {
    min-height: 100vh;
}

a {
    color: var(--color-primary);
    text-decoration: none;
}

a:hover {
    text-decoration: underline;
}

input {
    font-family: inherit;
    font-size: inherit;
}

button {
    font-family: inherit;
    font-size: inherit;
    cursor: pointer;
}

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

.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 10px 20px;
    border-radius: var(--radius);
    font-weight: 500;
    border: none;
    transition: background-color 0.15s ease;
}

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

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

.btn-primary:disabled {
    opacity: 0.6;
    cursor: not-allowed;
}

.input {
    width: 100%;
    padding: 10px 14px;
    border: 1px solid var(--color-border);
    border-radius: var(--radius);
    outline: none;
    transition: border-color 0.15s ease;
    background: var(--color-surface);
}

.input:focus {
    border-color: var(--color-primary);
}

.card {
    background: var(--color-surface);
    border: 1px solid var(--color-border);
    border-radius: var(--radius);
    padding: 24px;
}

.error-message {
    background: var(--color-error-bg);
    color: var(--color-error);
    padding: 12px 16px;
    border-radius: var(--radius);
    font-size: 0.875rem;
}