body {
    font-family: 'Poppins', sans-serif;
    text-align: center;
    background: linear-gradient(135deg, #1d2671, #c33764);
    color: white;
    margin: 0;
    height: 100vh;
    display: flex;
    justify-content: center;
    align-items: center;
}

/* Card */
.container {
    background: rgba(255, 255, 255, 0.1);
    padding: 40px;
    border-radius: 20px;
    backdrop-filter: blur(15px);
    box-shadow: 0 8px 30px rgba(0,0,0,0.3);
    width: 320px;
}

/* Title */
h1 {
    font-size: 32px;
    margin-bottom: 10px;
}

/* Timer */
#timer {
    font-size: 65px;
    margin: 20px 0;
    font-weight: bold;
}

/* Buttons */
.buttons button {
    padding: 12px 18px;
    margin: 8px;
    border: none;
    border-radius: 10px;
    font-size: 15px;
    cursor: pointer;
    transition: 0.3s;
}

/* Individual button colors */
.buttons button:nth-child(1) {
    background: #00c853;
    color: white;
}

.buttons button:nth-child(2) {
    background: #ffd600;
}

.buttons button:nth-child(3) {
    background: #ff1744;
    color: white;
}

/* Hover effect */
button:hover {
    transform: translateY(-3px);
    box-shadow: 0 5px 15px rgba(0,0,0,0.4);
}

/* Study Time */
h3 {
    margin-top: 20px;
}

/* Progress Bar */
.progress-container {
    background: rgba(255,255,255,0.2);
    border-radius: 10px;
    height: 10px;
    margin-top: 20px;
    overflow: hidden;
}

.progress {
    height: 100%;
    width: 0%;
    background: #00e5ff;
    transition: width 1s linear;
}